Abstract
Purpose: :
A electrochromic device with a full-custom electronic driver where the transmittance may be changed by the patient for different illumination conditions has been developed and tested.
Methods: :
Electrochromic devices use a material that changes its spectral transmittance properties when a low voltage is applied. We have developed an integrated circuit based on a Programmable Controller (PIC) to control the devices, being the custom use as simple as a two-button system. Because of this, manual operation by the end-user is possible. Furthermore, easy to use software for ophthalmic professionals has been developed to program this device. A three-colour photodiode is inserted into the front of a pair of glasses, their signals are read by the PIC and the kind of illumination is detected. The PIC drives the electrochromic filters according to the ophthalmologist schedule programmed.
Results: :
The transmittance in electrochromic devices is controlled by the electronic driver which has been developed. The transmittance may be programmed by the ophthalmologist and changed by the patient for different illumination conditions.
Conclusions: :
Traditional solutions for low vision people is the use of several colored filters intended to improve visual acuity, like Corning 450, 511 or 527, named according to the initial cut-off wavelength. It is usual that vision impaired people use two or three of these filters for different illumination conditions. Low vision people may increase their skills by using light spectral selective filters based on electrochromic devices and a Controlled Programmable. Future trials include clinical tests.
Keywords: development • visual development • low vision