Search

Structurally simple low-temperature dashed test objects (miras) with elements at temperatures lower than ambient are presented. These devices are based on thermoelectric elements (Peltier modules) with interchangeable thermal-insulating substrates mounted on them. The substrates have rectangular openings and heat-emitting conducting layers applied to the surface. Experimental thermograms of the models of test-objects are presented. The proposed devices are designed to align thermal imaging systems. They enhance the possibilities of investigating such systems and can be applied either separately or within infrared collimators.

An image-classification algorithm based on an alphabet of local binary patterns is described. The efficiency of the proposed algorithm is demonstrated using a test image set of handwritten digits (MNIST). A comparison of the algorithm’s properties with similar results to those of convolutional artificial neural networks is presented.

The eye resolving power and human visual acuity are the most important parameters of physiological optics. In this study, we compare our results of psychophysics, subjective measurement of visual acuity, with the results of electrophysiological measurement, objective measurement of visual acuity using vanishing optotypes that differ in spatial (sharp or non-sharp) and semantic (animate or inanimate) properties. The subject is instructed to provide consciously the classification of images: are they sharp, or are they non-sharp. At the same time the subject unconsciously provides another classification: what objects presented to him as images are animate or inanimate. This unconscious classification was provided by the subject without instruction to do it, and it was independent of his conscious decisions made during testing of the presented images of the objects (sharp or non-sharp). We see the observer’s unconscious classification (animate or inanimate) only using electrophysiological measurements. The markers of unconscious recognition are the visual evoked potential components P200 and N170, recorded from the frontal brain area. The discovered effect works as an instrument for objective visual acuity measurements.

This study is devoted to the search for electrophysiological indicators of the human perception of a threat in a complex background target environment. It is shown that the human visual system can distinguish between threatening and nonthreatening stimuli at an unconscious level, and the primary stages of image processing are similar to those during conscious perception. An increase in the amplitude of the positive wave of the evoked potential with a latency period of 320 ms and a decrease in the amplitude of the electroencephalogram rhythms at a frequency of approximately 12 Hz in the range of 350–750 ms after presentation of a threatening stimulus can serve as electrophysiological indicators of unconscious perception. The results obtained are considered from the perspective of the matched filtration model.

This paper proposes a principle for synthesizing a complex target environment and identifies the optical masking characteristics for unconscious perception of a signal. A signal hidden by masking is supplied on the periphery of the field of view for a short time interval, unconsciously activating wide-angle human “periscopic vision” that possesses low spatial and high temporal resolution. In these studies, the selective attention of the narrow-angle central-vision channel with high spatial resolution was charged with a pseudotarget. We assumed that peripheral vision is capable at that instant of unconsciously perceiving signals hidden by a mask and storing them in memory. It was established that the unconscious low-frequency descriptions of the signals stored in memory influence decision making and control the operator’s involuntary motions under conditions of indeterminacy. Opponent-style implementation of the interaction of central and peripheral vision can serve as a pattern for further refining artificial control systems.