A5014059008- Visual perception and processing mechanisms
- Color Science and Applications
- Color perception and design
- Optical Polarization and Ellipsometry
- Calibration and Measurement Techniques
- Ophthalmology and Visual Impairment Studies
- Advanced X-ray Imaging Techniques
- Infrared Target Detection Methodologies
- Ocular and Laser Science Research
- Categorization, perception, and language
- Electron and X-Ray Spectroscopy Techniques
- Visual Attention and Saliency Detection
- CCD and CMOS Imaging Sensors
- Glaucoma and retinal disorders
- Spatial Cognition and Navigation
- Advanced Electron Microscopy Techniques and Applications
- Olfactory and Sensory Function Studies
- Advanced Optical Imaging Technologies
- Impact of Light on Environment and Health
- Optical measurement and interference techniques
- Gaze Tracking and Assistive Technology
- Retinal Imaging and Analysis
- Intelligent Tutoring Systems and Adaptive Learning
- Disaster Response and Management
- Advanced optical system design
University of Latvia
2013-2024
Latvia University of Life Sciences and Technologies
2019-2022
University of Fribourg
2019
Abstract As people age, they tend to spend more time indoors, and the colours in their surroundings may significantly impact mood overall well‐being. However, there is a lack of empirical evidence provide informed guidance on colour choices, irrespective age group. To work towards we investigated whether associations between emotions observed younger individuals also apply older adults. We recruited 7393 participants, aged 16 88 years coming from 31 countries. Each participant associated 12...
We produced a set of pseudoisochromatic plates for determining individual color-difference thresholds to assess test performance and properties, analyzed the results. report high validity classification ability deficiency type severity level (comparable that fourth edition Hardy–Rand–Rittler (HRR) test). discuss changes acceptable chromatic shifts from protan deutan confusion lines along CIE xy diagram, correlation red–green discrimination index. Color vision was tested using an Oculus HMC...
(1) Background: Saccadic eye movements are rapid aimed to position the object image on central retina, ensuring high-resolution data sampling across visual field. Although saccadic studied extensively, different experimental settings applied studies have left an open question of whether and how stimulus parameters can affect performance. The current study aims explore effect contrast spatial movement latency, peak velocity accuracy measurements. (2) Methods: targets levels were presented at...
palīdzību, kad attēls tiek rādīts
In the current study, we address phase retrieval of one-dimensional objects from near-field diffraction patterns using multiple-plane Gerchberg–Saxton algorithm, which is still widely used for retrieval. The algorithm was implemented in a low-cost digital signal processor capable fast Fourier transform Q15 arithmetic, by previously mentioned algorithm. We demonstrate similarity between objects, i.e., vectors cut out map tertiary spherical aberration retrieved and these are measured with...
The aim of the study is to determine best printing technology for creation colour vision deficiency tests. Valid tests protanopia and deuteranopia were created from perceived matching experiments printed samples by deficient individuals. Calibrated EpsonStylus Pro 7800 printer ink prints Noritsu HD 3701 digital photographic used. Multispectral imagery (by tunable liquid crystal filters system CRI Nuance Vis 07) data analysis show that in case prints, measured pixel coordinate dispersion (in...
(1) Background: in this research study, colour vision was evaluated individuals aged 19 to 70 years with and without red-green disorders. (2) Methods: study participant assessed anomaloscope, HRR, FM100 hue, CAD tests. (3) Results: No significant correlation found between age chromatic sensitivity of the opponent channel. However, a decrease blue-yellow channel confirmed hue test test. Analysis error scores across groups revealed decline short-wave region visible light increasing age....
ABSTRACT Spectral and switching characteristics of two manufacturer liquid crystal goggles are tested. Experimentally the human stereovision acuity threshold were studied for case, when one eye random dot stereo stimulus simulated on display is continuously blurred or contrast decreased. In order to determine artefacts channel crosstalk stereostimuli separation ratio limits computer phosphors wavelengths determined. Keywords: gogglesspectral characteristicstemporal characteristicsvision...
Color of objects is a spectral composition incident light source, reflection properties the object itself, and tuning eye. Light sources with different characteristics can produce metameric representation color; however most variable in this regard vision. Pigments color vision are continuously bleached by stimuli optical density pigment changed, while continuous conditions provide an adaptation perception white. Special cases deficiencies which cover almost 8 % male population Europe....
Color deficiency tests are usually produced by means of polygraphy technologies and help to diagnose the type severity color deficiencies. Due different factors, as lighting conditions or age test, standard characteristics these fail, thus not allowing diagnosing unambiguously degree deficiency. Multispectral camera was used acquire spectral images Ishihara Rabkin pseudoisochromatic plates in visible spectrum. Spectral data converted cone signals, successive mathematics applied provide a...
The aim of the study is to determine consistency desired colour reproduction stimuli using calibrated printing technology available anyone (EpsonStylus Pro 7800 printer was). 24 vision assessment plates created in University Latvia were analysed right after their fabrication on august 2012 and intense use for 7 months (colour screening 700 people). Multispectral imagery results indicate that alignment samples seven has maintained CIExy confusion lines deutan deficiency type, but shift...
Aberrations impact A/V ratio calculated from full width at half maximum. We investigated whether aberrations affect by tracking the vessels. changed ratio. conclude that
The strength of chromatic after-effect was studied using the filling-in aftereffect image illusion (Van Lier et al.).In our experiments, two stimuli, each consisting round and sharp-edged overlapping shapes, were presented to subjects for 1.2 s on both sides fixation point.After that empty shapes stimuli appeared 0.6 s, in next changed orientation point thus changing color from side side.The made judgments about perceived a tengrade scale different pairs.The one stimulus kept constant, while...
Amorphous chalcogenide thin films are excellent materials for holographic recordings. AsSeS film coating is a useful optical material it's thickness to be easily corrected with the use of exposure light and consecutive chemical etching. Following properties allow treat surface them in adaptive optics systems correction wavefront. Hereby, we characterize used aberrations human eye. The characterized method spectrodensitometry profile depth Hartman- Shack waveform analyzator.
ABSTRACT Ferroelectric Liquid Crystal (FLC) filters offer the speed of electronic light shutters and vibration free operation. These characteristics make them ideal for applications requiring short exposure times minimal blur, offering switching 0.0002 a second. FLC can be used as optical machine vision purposes, also in research. On basis we have developed ferroelectric glasses, allowing temporal separation information both eyes. In case amblyopia (“lazy eye”) only way to oblige “lazy” eye...
We simulate vitreous floaters in a model eye and apply phase retrieval algorithm to recover the structure of floaters. The requires modulating object under study by relatively small number masks. masks are generated spatial light modulator. retrieved is compared that measured with surface profiler. It can be concluded presence speckles, however, high computational load one most significant drawbacks algorithm. In order proposed method for real-time correction floaters, speed must increased...
Automatic dynamic infrared retinoscope was developed, which allows to run procedure at a much higher rate. Our system uses USB image sensor with up 180 Hz refresh rate equipped long focus objective and 850 nm light emitting diode as source. Two servo motors driven by microprocessor control the rotation of semitransparent mirror motion chassis. Image eye pupil reflex is captured via software analyzed along horizontal plane. Algorithm for automatic accommodative state analysis developed based...