Continuous recording of accommodation and pupil size using the Shin-Nippon SRW-5000 autorefractor.
A newly released commercial autorefractor, the Shin-Nippon SRW-5000 (Japan), has been found to be valid compared to subjective refraction and repeatable over a wide prescription range. Its binocular open field-of-view allows the accommodative state to be monitored while a natural environment is viewed. In conventional static mode, the device can take up to 45 readings in 1 min using digital image analysis of the reflected retinal image of a measurement ring. Continuous on-line analysis of the ring provides high (up to 60 Hz) temporal resolution of the refractive state to an accuracy of < 0.001 D. Pupil size can also be analysed to a resolution of < 0.001 mm. The measurement of accommodation and pupil size was relatively unaffected by eccentricity of viewing up to +/- 10 degrees and instrument focusing inaccuracies of +/- 5 mm. The resolution properties of the analysis are shown to be ideal for measurement of dynamic accommodation and pupil responses.
Wolffsohn
J S
JS
Neurosciences Research Institute, School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK. j.s.w.wolffsohn@aston.ac.uk
Gilmartin
B
B
Mallen
E A
EA
Tsujimura
S
S
D000065:Accommodation, Ocular / Q000502:physiology*; D006801:Humans; D009885:Ophthalmology / Q000295:instrumentation*; D011680:Pupil / Q000502:physiology*; D012030:Refractive Errors / Q000175:diagnosis; D015351:Vision Screening / Q000295:instrumentation* / Q000592:standards