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Background: Helping upper elementary and lower secondary school students develop an awareness of various aspects of the nature of science (NOS) and nature of technology (NOT) is a widely recognized goal of science teaching. In this study, we focus on the connections between science and technology (S&T). Purpose: We report on the design, development, enactment and evaluation of a teaching-learning sequence (TLS) that combines hands-on activities in geometrical optics with explicit epistemological discourse for reflection purposes. The design of the TLS draws on perspectives from the inquiry-oriented and design-based teaching and learning frameworks. Sample: The enactment of the TLS involved a class of 17 sixth-grade students, aged 10-11 years old, of a public elementary school in Cyprus. Design and methods: We present findings from written responses to both closed and open-ended tasks as well as follow-up semi-structured interviews that probed students' understanding of the difference between the main goals of S&T. Results: The results illustrate elementary students' readiness to engage with epistemic issues and demonstrate the potential of prompting young learners' ability to develop informed awareness of the NOS and NOT. The results also provided feedback for the revision of the TLS so as to further enhance its effectiveness in achieving the stated learning objectives. Conclusion: We discuss the implications of our findings for the teaching of the NOS and NOT and for the design and validation of TLSs. It is possible for students of this age group to develop an awareness of issues related to the NOS and NOT. TLSs can be improved through design-based research approaches to serve as productive tools to this end.

In a university third-year instrumental chemistry laboratory students build a laser based polarimeter for determining light scattering with commercially available optical components used in modern optics research laboratories. During this laboratory experiment, students learn that solutions containing molecules which scatter light also influence the polarization properties of the laser beam by measuring Stokes parameters to calculate the degree of linearly polarized light. They also discover how the polarization properties of a laser beam are affected by half- and quarter-wave plates. Lastly, students are asked to recognize and assess the sources of error associated with the experiment including background intensity, integration time, and polarizer angle accuracy when measuring the Stokes parameters. A majority of students who completed the experiment agreed that this laboratory experiment required more critical thinking than traditional building instrumentation modules that they were exposed to, and that it improved their ability to learn independently and perform research.

Sometimes it takes little to keep this physicist happy on an airplane. A window seat, where the plane's shadow is visible or has disappeared into the distance, provides the opportunity to observe a variety of phenomena associated with sunlight that is reflected, refracted or scattered back towards the Sun. The term "backscattering" is often used to describe these phenomena. The Sun, me, and my position in the plane's shadow (called the antisolar point) are all in a line. The backscattering phenomena are at or centered on the antisolar point for the observer. If you can see clouds and their shadows on the ground, figure out where you must look to see a cloud cover its own shadow. That is where you must fix your attention to see these phenomena.

The notion of design research entails research where design practice forms part of the knowledge production. Based on our characterization of the nature of design, we propose to conceptualize this kind of research as programmatic design research. Two ongoing PhD projects in interaction design are presented as examples of programmatic research processes, highlighting issues to do with the virtues and qualities of the processes, the interplay of optics and engagements in a hermeneutical dynamic, and the production of takeaways for the academic community.

Research on the learning and teaching of science is an important field for scholarly inquiry by faculty in science departments. Such research has proved to be an efficient means for improving the effectiveness of instruction in physics. A basic topic in introductory physics is used to illustrate how discipline-based education research has helped identify certain conceptual and reasoning difficulties that are common among university students and pre-university teachers. The results have been used to guide the design of instruction that has brought about a significant improvement in learning. The type of research illustrated requires a deep knowledge of physics and ready accessibility to students as they study that subject. Both of these conditions are usually present only in physics departments, not in departments in which the primary focus is on educational theory and methodology. Although the context of this paper is physics, analogies can readily be made to other sciences.

The transfer of knowledge is considered to be a fundamental goal of education; therefore, knowing and understanding the conditions that influence the efficiency of the transfer from learning activity to problem solving play a decisive role in the improvement of science education. In this article, the results of a study of 196 high school students' ability to transfer knowledge in explanatory model construction are present. Three test groups were formed, traditional, prediction and lab groups, in which students were involved in three different learning activities. A week after instruction, students were tested with a foil test and Lawson's Classroom Test of Scientific Reasoning. According to the results, little knowledge transfer from learning activities to the foil test occurred. Among the three tested learning methods, the one asking for prediction seems to best improve the transfer of knowledge. Time spent on activities had little or no effect on the transfer of knowledge. Some possible reasons for the observed results are presented, and the importance of correct scientific explanation during the learning process is considered.

Active learning is individual and group participation in effective activities such as in-class observing, writing, experimenting, discussion, solving problems, and talking about to-be-learned topics. Some instructors believe that active learning is impossible, or at least extremely difficult to achieve in large lecture sessions. Nevertheless, the truly impressive implementation results of the SCALE-UP learning environment suggest that such beliefs are false (Beichner et al., 2000). In this study, we present a design of an active learning environment with positive effect on students. The design is based on the following elements: (1) helping students to learn from interactive lecture experiment; (2) guiding students to use justified explanation and prediction after observing and exploring a phenomenon; (3) developing a conceptual question sequence designed for use in an interactive lecture with students answering questions in worksheets by writing and drawing; (4) evaluating students' conceptual change and gains by questions related to light reflection, refraction, and image formation in an exam held a week after the active learning session. Data were collected from 95 science freshmen with different secondary school backgrounds. They participated in geometrical optics classes organized for collecting research results during and after only one active learning session. The results have showed that around 60% of the students changed their initial alternative conceptions of vision and of image formation. It was also found that a large group of university students is likely to be engaged in active learning, shifting from a passive role they usually play during teacher's lectures.

When driving on a sunny day, one can sometimes observe a small solar spectrum in the rearview mirror of a vehicle. The formation of this "rainbow" results from the prism-like structure of the rearview mirror. Our investigation of this phenomenon reveals that the resulting spectrum is formed in a manner similar to the way a rainbow is formed by a water droplet. We suggest a demonstration that you can perform so that your students can observe this phenomenon. All that is required is a sunny day, a ring stand, a clamp holder, and rearview mirror.

Nowadays more than two billion people own smartphones, without necessarily realizing they have a mobile physics lab that can be used to study acoustics, mechanics, astronomy, optics, fluids mechanics, or even serves as an oscilloscope. All smartphones have at least one camera, which is probably the most well-known and used sensor of this device. It allows us to take pictures, videos, to scan QR codes, etc. In this article, we show how to study simple ray optics with smartphones and how to determine the focal length of the smartphone camera, which could be an interesting and interactive way to introduce ray optics concepts.

Fitness centers and retail stores have often been accused of using "thinning" mirrors to enhance the images of their clientele. In this paper, the authors build a flatness gauge and use it to measure the curvature of the mirrors at a local fitness center. From these measurements, the image enhancement properties of the mirrors can be determined. The mirrors are found to be thinning, widening, and neutral with no apparent intent in their use or placement.

Physics educators around the world often need reliable diagnostic materials to measure students' understanding of physics concept in high school. The purpose of this study is to evaluate a new diagnostic tool on High School Optics concept. Test of Conceptual Understanding on High School Optics (TOCUSO) consists of 25 conceptual items that measures fundamental topics learned in high school curriculum. TOCUSO was designed with the use of various Optics textbooks, Turkish University exam questions, and questions generated by the author. TOCUSO items were structured as multiple-choice questions. 12 physics faculty members at the school of science and education validated questionnaire items. SPSS program was utilized to calculate reliability values of the test. KR-20 value was found around 0.73, which shows TOCUSO is a reliable measurement questionnaire. TOCUSO was applied to 183 high school students enrolled in 10th grade at the time of data collection process in Kayseri providence in Turkey.

The study of shadows is a common elementary science topic that facilitates students' development of understanding about light and associated waves. All elementary students have observed numerous shadows, but need assistance in developing understanding. Previous research studies about shadows were utilized in organizing aspects associated with shadows. This review paper encourages teachers to utilize three principles of learning: students' prior knowledge about shadows, factual and conceptual knowledge related to shadows, and metacognition requiring students to think about their personal understanding about shadows; thereby, promoting students' science literacy.

Light polarization, which is the direction of electromagnetic field oscillation, provides information that is highly different from that of spectral and intensity images and thus can enhance various fields of optical metrology. Polarization imaging can be also used by combining polarization and imaging, thereby providing polarization and spatial information. In university physics teaching, light polarization is limited to the understanding of the polarization state of a single beam and polarization imaging is rarely involved. Here we use the camera of a smartphone, a polarizer, and 3D printing components to create a simplified imaging polarimeter, thus showing the characteristics of polarization imaging and its application.

In this article a thin optical lens model is considered. It is shown that the limits of its applicability are determined not only by the ratio between the thickness of the lens and the modules of the radii of curvature, but above all its geometric type. We have derived the analytical criteria for the applicability of the model for different types of lenses. Quantitative estimations were made for practically important cases ?f a glass lens in air and air lens in water.

The field of electrical and computer engineering has evolved significantly in the past two decades. This evolution has broadened the field of ECE, and subfields have seen deep penetration into very specialized areas. Remarkable devices and systems arising from innovative processes, exotic materials, high speed computer simulations, and complex algorithms make ECE an exciting career field. These fascinating developments present greater opportunities for undergraduates to explore the field of ECE as well as greater challenges for them to navigate the curriculum because of the myriad of course and areas of concentration choices they have to make. Reflecting innovations in the field and capitalizing on the collective faculty research expertise, the Department of Electrical and Computer Engineering at Duke University has redesigned its undergraduate curriculum around the theme of "Integrated Sensing and Information Processing." This paper presents details of the ECE curriculum redesign at Duke University including its philosophy and implementation as well as elements of the redesign that are transferable to other universities. Evidence of increased student ability to design a system or component and to work effectively in teams is presented through statistical analyses of student end-of-course course evaluations. Student design project complexity evolution as the curriculum redesign unfolded is also presented, and this provides further evidence that design and teamwork have enhanced student learning throughout the new curriculum.

In this paper we propose adapting role-play teaching methodology to engineering studies. The role of a maintenance technician, a relevant job profile for engineering graduates is has chosen. The interaction is based on email exchange, with the instructor included in the simulation to help guide the activity and achieve learning objectives. In this paper, we present experience with this methodology, its implementation, results, and student feedback.

The study of pupils' representations of physics concepts and phenomena constitutes a central part of Science Education research, as they play a decisive role in teaching. In the study presented here, we investigate 212 fifth grade pupils' mental representations of the formation of shadows, before they were taught about it in school. The empirical data was gathered through an interview using four tasks which involved the evaluation of hypothetical situations. The research data included representations that cause difficulty in the comprehension of the position of a light source in relevance to the shadow.

In their paper the authors deal with the vital issues of creation and application of electronic teaching materials for natural science subjects teaching. They describe an experimental examination of qualitative impact of these aids on education. The authors present a part of research results, which they obtained in a major research focused on possibilities to influence students' attitudes and approaches to particular subjects, mainly the less favorite ones. To be more specific they deal with possibilities to eliminate students' very negative attitude to physics. Their target group were 17-19 aged students and the means applied to change the attitudes of this group to physics were specially designed multimedia education materials and interactive flash animations "Principles of Geometry Optics" covering basic topics from geometry optics.

This study examined growth in graphical literacy for students contributing to an online, multimedia, communal environment as they advanced their understanding of biology, history and optics. Their science and history studies started early in Grade 3 and continued to the end of Grade 4; students did not receive instruction in graphics production, nor were they required to produce graphics. Results show that students spontaneously produced graphics that advanced along seven dimensions, including effective representation of complex ideas, use of source information and captions, and aesthetic quality. On average, the scores for the seven dimensions were higher for Grade 4 students with two years of experience with Knowledge Building pedagogy and technology (Knowledge Forum[R]) than for Grade 6 students with one year of experience. The overall pattern of results suggests reciprocal enhancement of graphical, textual, digital, and scientific literacy, with students exceeding expectations by available norms, and performance enhanced through extended Knowledge Building experience. (Contains 6 figures and 2 tables.)

The wide-spread digital photography and computer use gave the opportunity for everyone to make three-dimensional pictures and to make them public. The new opportunities with three-dimensional techniques give chance for the birth of new artistic photographs. We present in detail the biological roots of three-dimensional visualization, the phenomena of movement parallax, which can be used efficiently in making three-dimensional graphics, the Zöllner- and Corridor-illusion. There are present in this paper the visual elements, which contribute to define a plane two-dimensional image in three-dimension: coherent lines, the covering, the measurement changes, the relative altitude state, the abatement of detail profusion, the shadings and the perspective effects of colors.

Young's experiment is hailed as a milestone in ushering a new understanding of the wave nature of light and is even taught at the high school level. Unfortunately, even the most cursory presentation of the subject of diffraction becomes confusing. The theory and equations based on Fresnel's work appear arcane and incomprehensible to a high school student. In addition, students are "not" taught the significance of a phenomenon that has been observed since the time of Thomas Young: the bright band of light at the center of every single slit diffraction pattern. This paper presents a simple way to introduce the subject of diffraction based on Thomas Young's original work and explains how the interplay of different components of diffracted waves from a single slit creates the broad central maximum.

Excel spreadsheets are used as an excellent tool in physics laboratory experiments related to wave optics. This paper presents a simple way to simulate diffraction of waves through a slit using Excel spreadsheets without any tedious programming. These simulations are used to visualize the effect of variation of different parameters such as number of slits, wavelength of incoming light, slit width and slit separation on Fraunhofer diffraction pattern.

To improve the teaching and learning materials for a curriculum it is important to incorporate the findings from educational research. In light of this, we present creative exercises and experiments to elicit, confront and resolve misconceptions in geometrical optics. Since ray diagrams can be both the cause and the solution for many misconceptions we focus strongly on improving understanding of this tool to solve and understand optical phenomena. Through a combination of a conceptual understanding programme (CUP) and provocative exercises with ray diagrams we aim to elicit conceptual or cognitive conflict and exploit this to tackle misconceptions and increase students' conceptual understanding through inquiry. We describe exercises for image formation by a plane mirror, image formation by a convex lens and indirect and direct observation of a real image formed by a convex lens as examples of our approach.

The infrared camera is a useful tool in physics education to 'see' in the infrared. In this paper, we describe four simple experiments that focus on phenomena related to heat transfer and optics that are encountered at undergraduate physics level using an infrared camera, and discuss the strengths and limitations of this tool for such purposes.

The purpose of this paper is to present and discuss an alternative solution to an experimental problem given to high school students in the XXII Ibero-American Physics Olympiad held by Colombia this year. From the measurements of electric current and potential difference across a small tungsten filament lamp students should find the dimensions of its filament. The results obtained are compared with the ones measured directly. This challenging and low-cost experiment can be easily implemented and carried out in any introductory physics laboratory courses.

In 1849, Hippolyte Fizeau determined the speed of light in a famous experiment. The idea was to measure the time taken for a pulse of light to travel between an intense light source and a mirror about 8 km away. A rotating cogwheel with 720 notches, that could be rotated at a variable speed, was used to chop the light beam and determine the flight time. In 2017, physicists and technicians of the University of Mons in Belgium reproduced the experiment with modern devices to allow members of the public to measure the speed of light themselves. The light source used was a low power laser, and the cogwheel was replaced by an electrically driven chopper, but the general spirit of Fizeau's experiment was preserved. The exhibition was organised in the belfry of Mons, a baroque-style building classified as a UNESCO World Heritage site. The solutions found for the main problems encountered are presented here to help colleagues intending to reproduce the experiment.

We propose the use of a smartphone based apparatus as a valuable tool for investigating the optical absorption of a material and to verify the exponential decay predicted by Beer's law. The very simple experimental activities presented here, suitable for undergraduate students, allows one to measure the material transmittance including its dependence on the incident radiation wavelength.

Additive manufacturing (3D printing) is a technology with near-unlimited potential for the chemical educator. However, its adoption into higher education has been limited by the dual requirements of expertise in 3D printing and 3D computer-aided design (CAD). Thus, its reported utilization in the chemistry curriculum has been within the creation of 3D models for the macroscopic visualization of molecular models and processes. With the commercialization of inexpensive 3D printers, we seek to provide a series of optical mounts and tools for use in chemical research or education by designing systems which may be mounted on a breadboard and used to construct chemical instrumentation. These designs include mounts for cylindrical lenses or mirrors with 0.5, 1, and 2 in. diameters, 0.5 in. diffraction gratings, an adjustable optical slit, cuvette holders, stepper motor (NEMA 17) adapters, and a modular, 3D printed breadboard. All designs were created using Solidworks CAD, and have been provided in Supporting Information and uploaded to https://github.com/EdavisAPU/Education-Optics in both Solidworks native format (*.SLDPRT) and a standard file exchange format for 3D objects (*.STL) format for use, modification, or collaboration. All files are released under the MIT Open-Source license (modified for Design). In comparison with commercially available products, the prototypes presented herein provide significant cost-savings, with many designs 1-2 orders of magnitude cheaper than commercial equivalents. In addition, these designs have been utilized in an upper division instrumental analysis course as students designed and constructed a visible spectrophotometer using these optical devices. Data from the resultant instrument is presented and compared with a commercially available spectrophotometer.

A surprising phenomenology from a traditional demonstration experiment in Geometrical Optics reveals here an interesting matter of discussion and analysis. Hence, the main focus of this paper is to observe and discuss such an innovative phenomenology.

The topic of refraction and reflection of light at the boundary of transparent media is a fundamentally important one. The special case of total internal reflection is however commonly misrepresented in elementary textbooks. This paper addresses the problem and describes an experimental procedure for measuring and displaying reflected and transmitted light intensities using readily available components and the Arduino microcontroller.

This study investigated how managers, entry-level employees, and hiring professionals in the optics and photonics industry socialize each other to enact the communication norms and expectations in their workplaces. A qualitative analysis of transcripts from interviews conducted with 33 employees at 15 companies produced five prevalent themes related to what optics and photonics employees consider competent communication (proactive questioning, efficient decision-making, familial-like humor, tactful translation, and fluent modality switching) and three socialization processes (presumed competence, informal mentoring, and structured training). These competencies and processes necessitate what we term "cross-occupational communication": an interactive, iterative process involving communicative needs assessment, information exchange, and rhetorical/situational flexibility with groups distinct in background, training, and occupational role. It is difficult to create workplace-like experiences that truly capture the field-specific communication practices involved in organizational socialization within traditional classrooms; therefore, we argue for systematic and intentional communication in the disciplines instruction that considers cross-occupational communication needs in the workforce.

The ability to develop, use, and refine models of experimental systems is a nationally recognized learning outcome for undergraduate physics lab courses. However, no assessments of students' model-based reasoning exist for upper-division labs. This study is the first step toward development of modeling assessments for optics and electronics labs. We interviewed 35 lab instructors about the ways they incorporate modeling in their courses, and we used their self-reported learning goals and activity designs to identify test contexts and objectives that are likely relevant across many institutional settings. The study design was informed by the Modeling Framework for Experimental Physics, which conceptualizes modeling as consisting of multiple subtasks: making measurements, constructing system models, comparing data to predictions, proposing causes for discrepancies, and enacting revisions to models or apparatus. We found that each modeling subtask was identified by multiple instructors as an important learning outcome for their course. Based on these results, we argue that test objectives should include probing students' competence with most modeling subtasks, and test items should be designed to elicit students' justifications for choosing particular modeling pathways. In addition to discussing these and other implications for assessment, we also identify future areas of research related to the role of modeling in optics and electronics labs.

Multimedia learning environments facilitate the construction of certain forms of representations and allow users to combine forms of representation that address different modalities. A promising approach entails having students construct representations of the domain. The process of constructing a representation elicits self-explanation effects and consists of dynamic iterations and interactions between the constructed representations and mental representations, and therefore helps students to refine and disambiguate their domain knowledge. Because mobile multimedia learning environments have enabled numerous new forms of presenting and communicating information, this study restores interest in the method of adopting mobile video conferencing in learning, and proposes its use in face-to-face collaborative learning of the first law of reflection in optics with the aim of harnessing the synergy of both communication modes. A total of 34 junior high school students participated in the study. The results showed that the participants acquired a new aspect of learning regarding the law of reflection, and their metacognitive awareness increased as a result of using the mobile video, which regulated their explorative learning process. This study provided an unprecedented and meaningful learning experience to students and stimulated teachers to explore the full potential of technologies around them in education.

Background: The development of context-based science curricula has been identified as one of the most effective curricular innovations to develop interest and better conceptual understanding of many areas in science. However, such a curriculum can be more fruitful if it starts with the assessment of learners' contextualized knowledge about the science topic in hand. Purpose: The focus of this paper is to investigate secondary school learners' knowledge of the optical phenomena of reflection and refraction in relation to certain contexts. Sample: The sample for the study consisted of two Grade-11 intact groups of 70 learners in total at a selected senior secondary school in the Mthatha District of the Eastern Cape Province in South Africa. Design and methods: The study focused on exploring the learners' conceptions about the optical phenomena of reflection and refraction. The data were collected from three two-tier questions, which exposed the learners to certain contexts which could be explained using optics principles. The first tier of each question was a context-based multiple-choice question and in the second tier, the participants were asked to justify their answers to the first tier. Results: Majority of the participants failed to correctly interpret the given contexts using optics principles. Moreover, only a few learners could justify their scientifically acceptable answers with scientifically acceptable explanations. Conclusions: The participants experienced serious conceptual difficulties when they were required to apply the optics concepts in the real-world contexts presented to them. Moreover, the participants' conceptual difficulties about reflection and refraction were also found to be associated with their inability to understand correctly the optical processes involved in vision.

This article proposes a practical method of teaching the addition of unit fractions using a series of mirror equation experiments.

In the current debate on pedagogical content knowledge (PCK), the term is used to refer to the context-specific knowledge that teachers activate when reflecting on practice. Against the background of this debate, we conducted an empirical study and sought to answer the question of which knowledge experts and novices activated in assessing a videotaped lesson in relation to its effectiveness for learning. Our assumption was that the participants activate their PCK as a blending of content knowledge (CK) and pedagogical knowledge (PK) as suggested by Shulman's amalgam thesis. The participants (9 experts and 9 novices) were shown a lesson on optics, in which the law of refraction (Snell's law) was being studied. In a subsequent interview, the participants were asked to analyze the observed lesson. A qualitative and quantitative evaluation of the interviews showed that experts activated both CK and PK intensively and in this respect they differed significantly from novices. Further analysis of the expert statements also proved that they do not activate their CK and PK in isolation, but instead combine both kinds of knowledge together, in line with Shulman's amalgam thesis.

A low-cost time-resolved emission spectrometer optimized for ruby emission is presented. The use of a Class II diode laser module as the excitation source reduces costs and hazards. The design presented here can facilitate the inclusion of time-resolved emission spectroscopy with laser excitation sources in the undergraduate laboratory curriculum. The ruby decay data show evidence of radiation trapping, an interesting optical phenomenon discussed in the research literature.

To prepare physics students for future careers, educators need to understand the skills and other factors necessary for entry and success on the job. Often these insights are based on CEOs, HR personnel, and managers, who provide broad perspectives regarding successful attributes of new hires. However, such insights are often more general and disconnected from specific jobs than insights gained from entry-level employees who recently transitioned from school to work. Using in-depth descriptive summaries and thematic analysis from interviews with six recently hired technicians and engineers in the field of optics, we explored factors that influenced their entry and success on the job. Six themes arose: documentation, computational skills, specialized learning, question asking, tinkering skills, and navigating cultural differences. We discuss the implications of these themes in both their value to employees as well as integration into the physics curriculum.

Background: Productive learning processes and good learning outcomes can be attained by applying the basic elements of active learning. The basic elements include fostering discussions and disputations, facing alternative conceptions, and focusing on conceptual understanding. However, in the face of poor course retention and high dropout rates, even learning outcomes can become of secondary importance. To address these challenges, we developed a research-based instructional strategy, the "primetime learning" model. We devised the model by organizing the basic elements of active learning into a theory-based four-step study process. The model is based on collaborative and technology-enhanced learning, on versatile formative assessment without a final exam, and on genuine teacher presence through intimate meetings between students and teachers. Results: We piloted the model in two university physics courses on thermodynamics and optics and observed persistent student activity, improved retention, and good learning outcomes. Feedback suggested that most students were satisfied with the learning experience. Conclusions: The model suits particularly well for courses that, in addition to the teaching subject itself, focus on teaching balanced study habits and strengthening social integration. By its very construction, it also helps the propagation of research-based instructional strategies. Although the model does contain challenges, it represents a generic framework for learning and teaching that is flexible for further development and applicable to many subjects and levels.

The present study investigated whether computer assisted instruction was more effective than face-to-face instruction in increasing student success in physics. The study was conducted in the spring semester of 2006 at the Department of Science and Mathematics for Secondary Education at Hacettepe University. Seventy-eight freshman students from the Divisions of Biology Education and Chemistry Education participated in the quantitative study which included a pre-test/post-test control group design. The experimental group consisted of students from the Division of Biology Education while the control group consisted of students from the Division of Chemistry Education. Experiment and control groups were randomly selected. The subject of geometric optic covered in Physics II Course was provided through a simulation program called Pearls 3.0 to the experiment group, whereas the control group had the same instruction through face-to-face teaching methods. An achievement test addressing the contents of the geometric optic subject was prepared, which had an internal consistency coefficient of .73. Data obtained through the achievement test were analyzed through conducting t-tests with SPSS 11.0 for Windows. Findings revealed that the experimental group which had the instruction through the computer simulation was more successful than the control group who had face-to-face instruction. (Contains 6 figures and 4 tables.)

When doing experimental work of image formation by mirrors and (thin) lenses, it turns out again and again that students often have partially incorrect preconceptions about how the light emerging from an object passes through a lens and how the image is formed on a screen or directly in the eye. To check students' prior knowledge and help get a better understanding of geometrical optics, we decided to start classes with a pre-test to assess their knowledge and understanding. Then we performed a series of experiments (to be described in the paper) with (thin) converging lenses, partially covered with either an opaque screen or with (one or more) color filters. In the end, students' knowledge and understanding were tested again with a post-test. The main goal of the experiments was to convey to students a clearer picture about the image formation, and to help them recognize the fact that every small part of a lens participates in the formation of the whole image.

Everyone who has visited an art museum and stood before a masterful painting has admired the artist's clever use of accurate perspective to bring a third dimension to the flat canvas. The mathematical theory of perspective is almost 600 years old, having been pioneered by Leon Battista Alberti (1404-1472) in his treatise "De Pictura" (1435). Standing in front of a painting, you usually give little thought about precisely where to stand, relative to the canvas, in order to appreciate the three-dimensionality of the scene. Yet Alberti writes, on p. 57, "Know that a painted thing can never appear truthful when there is not a definite distance for seeing it." You, the viewer, must assume the responsibility for accurately viewing the perspective intended by the artist. This article is intended to help viewers of art determine where to stand before a painting or a photograph. It is based on the idea from ray optics that light travels in straight lines from its source to the viewer's eye.

Deciding what should be included in a curriculum has long been a topic of controversy. The struggle to identify what should be taught in schools has been evident throughout the development of American schools and continues today. This article discusses the importance of needs assessment throughout the curriculum development process. Needs assessment is a powerful tool that can help clarify and validate true needs. Since a needs analysis collects information that can be used in making educational decisions, integrating needs assessment throughout the curriculum development process can help to assure that career and technical programs do not create an either-or situation but rather benefit both the learners and society.

Virtual reality (VR), as an emerging visualization technology, has introduced an unprecedented communication method for collaborative design. VR refers to an immersive, interactive, multisensory, viewer-centered, 3D computer-generated environment and the combination of technologies required to build such an environment. This article introduces the current status of VR applications in industry and the technologies involved in the low-cost VR systems. The number of companies producing low-cost VR-related hardware and software is continuously increasing. New hardware and software technical terms are confusing or meaningless to people without any prior background in VR. Thus, choosing the right VR tool for a particular application is challenging for potential users. This article introduces different available stereo image rendering techniques, such as anaglyphic, page flipping, and sync doubling, and major low-cost VR hardware and software tools available for CAD model viewing. The purpose of this article is to help CAD users and product designers have a better understanding about VR technology so that they can develop their own VR systems to increase the efficiency of design communication. (Contains 6 figures.)

The camera obscura is a well-known optical device in the form of a closed box with a hole in one of its walls through which light rays pass, forming an inverted image of the external objects on the opposite wall, as can be seen in Fig. 1(a). Despite the simplicity of its basic design, they have been widely used by scientists and artists. In particular, dark cameras have been used throughout history to measure Earth-Sun distance. To do this, ancient scientists used cameras of enormous dimensions to accurately measure the variations in the apparent diameter of the Sun that depend on the Earth-Sun distance. This is because the farther the light travels inside the camera, the larger the projected image will be [Fig. 1(b)]. In this work, the construction of a compact dark camera for educational purposes is presented so that, having reduced dimensions, it allows the images to be very large.

It is well known that when two waves are added they produce beats. These beats are the amplitude modulation of the initial waves and occur periodically at a rate equal to the frequency difference of the two waves. Acoustical beats arise from sound waves of nearly equal frequencies. Optical beats arise from the interference of two light waves of nearly equal frequencies. Despite these examples, adding two waves does not always create a new wave at the beat frequency--a heterodyne wave. A heterodyne wave is, however, created only when the wave amplitudes combine nonlinearly. The resulting heterodyne wave can be identified because it is an additive term at a new frequency in the output waveform. An electrical circuit provides a unique opportunity to understand the responses of linear and nonlinear devices (resistors and diodes) to the sum of two sinusoidal waves. Using the resistor, the output frequencies are the same while the diode creates new (heterodyne) frequencies. A speaker in the circuit provides an audio demonstration of the difference between the devices.

Ray diagrams are widely used in introductory physics textbooks to illustrate the behavior of ideal systems of lenses or mirrors in geometrical optics. Their virtue lies in their explicit display of multiple ray paths connecting object and image points, which leads naturally to an understanding of how a planar object is transformed into a planar image. This understanding is often followed by questions involving the "general" behavior of a lens. How do the image position and size change as the object is moved to different positions, or when the object also has significant axial depth? What image regions are visible for a particular lens aperture and eye position? Answering these questions using ray diagrams can be cumbersome, often requiring multiple diagrams with objects in different positions and leading to a fragmented understanding of lens behavior. This article illustrates how these kinds of questions can be addressed using a related visualization method I call an "image field diagram," which trades the explicit constructions of ray diagrams for a more general display of object-image pairs.