BS 3668 is a European standard that outlines the requirements for red and green filters of glass or plastics materials used in ophthalmic tests as follows:
BS 3668 on red and green filters used in ophthalmic dichromatic and dissociation tests is useful for:
Red and green filters are used in ophthalmic dichromatic and dissociation tests because the red filter blocks the green light and the green filter blocks the red light, it is possible to determine if the patient is using both eyes simultaneously and in a coordinated manner. With both eyes open, a patient with normal binocular vision will appreciate four lights.
BS 3668 guides you regarding the weighted spectral transmission and luminous transmission factor of filters for use in dichromatic tests. BS 3668 additionally, guides you regarding the spectral transmission, luminous transmission factor, and quality of viewing goggles filters for use in dissociation tests to obtain reliable results.
With obedience and compliance to BS 3668, you can enhance the efficacy of red and green filters used in ophthalmic dichromatic and dissociation tests. In addition, can ensure that test results are reliable and reproducible in other laboratories.