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Presented for the first time is a machine learning enhanced optical distance sensor. The distance sensor is based on our previously demonstrated distance measurement technique that uses an Electronically Controlled Variable Focus Lens (ECVFL) with a laser source to illuminate a target plane with a controlled optical beam spot. This spot with varying spot sizes is viewed by an off-axis camera and the spot size data is processed to compute the distance. In particular, proposed and demonstrated in this paper is the use of a regularized polynomial regression based supervised machine learning algorithm to enhance the accuracy of the operational sensor. The algorithm uses the acquired features and corresponding labels that are the actual target distance values to train a machine learning model. The optimized training model is trained over a 1000 mm (or 1 m) experimental target distance range. Using the machine learning algorithm produces a training set and testing set distance measurement errors of

Proposed is a single viewing axis optical Three-Dimensional (3-D) shape sensor using an electronically controlled variable focus lens (ECVFL) for non-contact smallest transverse resolution reconstructions at all axial direction target planes. The demonstrated completely automated sensor design also involves input beam aperture control for balancing aberration and diffraction effects, enabling minimum focused sampling beam diameter. Sensor design analysis is presented, including the derivation of the depth of field of the camera used in the 3-D sensor. A computer-controlled sensor system using a liquid ECVFL is built and experimentally calibrated for a 40-mm-depth scan with a better than $52~\mu \text{m}$ transverse resolution over a $400~\textrm {mm} \times 400$ mm mechanically implemented transverse scan zone. The 3-D sensor system is successfully deployed to measure the borehole depths in a 3-D sample containing 12 boreholes, image the pin regions of a 16-pin Integrated Circuit (IC) Thin-Shrink Small Outline Package (TSSOP), and reconstruct the shape of a 3-D aircraft part. The sensor gave a ±3% average measurement error for the borehole test sample compared with a vernier caliper measurement. The proposed single viewing axis sensor is ideal for applications requiring cavity or borehole inspections as well as parts requiring high transverse resolution imaging.

Presented is an active no moving parts Depth From Defocus (DFD) system for autofocus and three-dimensional (3-D) imaging applications. The proposed system uses highly coherent laser light and its beam conditioning optics to realize an active illumination system suited for long range and large field of view imaging, overcoming the limited field of view in previous active DFD systems. This is the first time an active DFD system is implemented and experimentally demonstrated using an Electronically Controlled Variable Focus Lens (ECVFL) as an imaging lens that electrically varies the focal length to acquire images with different degrees of defocus, necessary for DFD operations. An experimental demonstration of the proposed system acting as a distance sensor is compared to an incoherent illumination projector DFD system tested over a 1 m range. Apart from showing the effectiveness of the ECVFL as an imaging optic for cameras implementing DFD based autofocus algorithms, presented experimental results for the novel system indicate a depth measurement percentage error of

Proposed is a novel eye vision testing system based on micromachines that uses micro-optic, micromechanic, and microelectronic technologies. The micromachines include a programmable micro-optic lens and aperture control devices, pico-projectors, Radio Frequency (RF), optical wireless communication and control links, and energy harvesting and storage devices with remote wireless energy transfer capabilities. The portable lightweight system can measure eye refractive powers, optimize light conditions for the eye under testing, conduct color-blindness tests, and implement eye strain relief and eye muscle exercises via time sequenced imaging. A basic eye vision test system is built in the laboratory for near-sighted (myopic) vision spherical lens refractive error correction. Refractive error corrections from zero up to −5.0 Diopters and −2.0 Diopters are experimentally demonstrated using the Electronic-Lens (E-Lens) and aperture control methods, respectively. The proposed portable eye vision test system is suited for children’s eye tests and developing world eye centers where technical expertise may be limited. Design of a novel low-cost human vision corrective eyewear is also presented based on the proposed aperture control concept. Given its simplistic and economical design, significant impact can be created for humans with vision problems in the under-developed world.

To the best of the authors’ knowledge, proposed is the first embedded optics and electronics-based agile pixel broadband optical imager and spectrum analyzer using a single digital micromirror device (DMD) for laser beam hotspot detection. Specifically, the novel design engages both the wavelength-dependent grating structure of the DMD optical chip and its three-tilt-state micromirror programmability to form both an optical spectrum analyzer (OSA) and an agile pixel imager within one basic instrument. Also, to our knowledge, presented for the first time for a DMD chip is a complete mathematical analysis for incident laser beam operations via diffraction theory. Using off-the-shelf components and the Texas Instruments (TI) Lightcrafter DLP chip and drive electronics, embedded engineering of the proposed instrument is implemented for the visible laser wavelength band. Experimental OSA operation of the instrument is demonstrated using classic laser wavelengths of 633 and 532 nm with beam power levels of 20 and 180 mW, respectively. Experimental imaging operation of the instrument compared with a commercial scanning slit-based laser beam profiler is successfully conducted for a 633 nm test laser beam having a hotspot with ∼68% peak-to-null power drop near its center. Applications for the proposed imager-OSA instrument include laser beam testing during laser assembly and manufacturing operations.

A smart laser scanning sampling head design is presented using an electronically controlled variable focal length lens to achieve the smallest sampling laser spot possible at target plane distances reaching 8 m. A proof-of-concept experiment is conducted using a 10 mW red 633 nm laser coupled with beam conditioning optics that includes an electromagnetically actuated deformable membrane liquid lens to demonstrate sampling laser spot radii under 1 mm over a target range of 20-800 cm. Applications for the proposed sampling head are diverse and include laser machining and component inspection.