0000000000354712
AUTHOR
Renārs Trukša
Rayleigh Equation Anomaloscope from Commercially Available LEDs
Most precise classification of CVD (color vision deficits) can be provided by using anomaloscope. Today anomaloscopes are available, which can evaluate red-green (Rayleigh) and blue-green (Moreland) color defects.DOI: http://dx.doi.org/10.5755/j01.ms.18.2.1928
Adaptācijas ietekme uz datorizēta krāsu redzes un anomaloskopa testa rezultātiem
Darba mērķis: noskaidrot apgaismojuma līmeņa un adaptācijas ietekmi uz datorizētā krāsu redzes testa un anomaloskopa testa rezultātiem. Metode: Hromatiskās jutības noteikšanai tika izmantots autora izveidots datorizēts krāsu redzes tests, testa dalībnieku krāsu redzes rakstura izvērtēšanai tika izmantots anomaloskops OCULUS HMC un HRR pseidoizohromatiskās kartes. Adaptācijas stimulu ģenerēšanai tika izmantota autora izveidota iekārta. Rezultāti: Tika noskaidrots, ka apgaismojuma līmenim nav būtiskas ietekmes uz datorizētā krāsu redzes testa un anomaloskopa testa rezultātiem. Testa stimuli robežās no 4,22 līdz 9,83 grādiem redzes lauka būtiski neietekmē datorizētā krāsu redzes testa rezultāt…
Differences in Chromatic Sensitivity Estimated Using Static and Dynamic Colour Stimuli
Abstract The current study reports on a novel computerised colour vision test employing static and dynamic stimuli. The aim of the study was to assess if static and dynamic stimuli result in comparable chromatic discrimination thresholds when participant’s age is taken into account. Participants (n = 20) were 21 to 77 years old, had normal colour vision and no history of any eye disease. They all participated in two sessions estimating chromatic sensitivity with static and dynamic stimuli, respectively, with six directions in colour space varying either along the red-green (RG) or yellow- blue (YB) directions. We found no significant differences in chromatic thresholds along a tritan axis o…
Algorithms for skiascopy measurement automatization
Automatic dynamic infrared retinoscope was developed, which allows to run procedure at a much higher rate. Our system uses a USB image sensor with up to 180 Hz refresh rate equipped with a long focus objective and 850 nm infrared light emitting diode as light source. Two servo motors driven by microprocessor control the rotation of semitransparent mirror and motion of retinoscope chassis. Image of eye pupil reflex is captured via software and analyzed along the horizontal plane. Algorithm for automatic accommodative state analysis is developed based on the intensity changes of the fundus reflex.