Analysis of intraocular straylight, especially in relation to age.

PURPOSE

To analyze straylight resulting from different sources (cornea, lens, wall translucency, and fundus reflectance) in combination with different properties (age and pigmentation). To give formulas for straylight calculations.

METHODS

In straylight on the retina multiple scattering can be assumed to be unimportant. Consequently, an additive model can be applied.

RESULTS

An efficient parameter to quantify straylight is the "straylight parameter" s(theta), with theta the scatter angle. The model reads s(theta) = s(cornea)(theta) + s(lens)(theta) + s(wall)(theta) + sfundus(theta), and each of these sources is analyzed as sx(theta) = sx,base(theta) + a(age)*sx,age(theta) + p(pigm.)*sx,pigm.(theta).

CONCLUSIONS

The most important effects, viz., s(lens,age), s(wall + fundus,pigm.) and s(cornea + lens + fundus,base) as well as a(age) and p(pigm.) were estimated. With the straylight parameter different effects of straylight, notably its disabling effect of contrast reduction, follow directly.