Pinhole Spectacles The following extract is taken from "The Optometrist's Handbook of Eye Diseases", written by Joseph I. Pascal and Harold G. Noyes.

Another aid for both distant and near vision is the pinhole or rather the multiple pinhole spectacle, frequently called Stenopeic Spectacles.  These Stenopeic spectacles are especially useful where there are diffuse opacities in the ocular media, cornea, lens, or vitreous.  They are also applicable in cases of marked irregularities of the refractive media of  the eye.  In such cases they sometimes improve vision both for far and near beyond what can be accomplished with magnifying devices or contact lenses.  The pinhole acts as a fixed focus device for both far and near.

Occasionally, a combination of a magnifying device with a pinhole spectacle is used, the former to enlarge the retinal image, the latter to produce a sharper retinal image free from veiling glare.  Other combinations such as contact lenses for conical cornea and a magnifying device to enlarge the retinal image are sometimes used.  Here the contact lens can be made to act as the ocular of a telescopic spectacle, and thus serve a double purpose.

Another aid that is used occasionally is a stenoic slit, similar to the slit found in the trial case.  It can be set in the position found to give best vision and mounted on a regular frame.  The use of side-shields on spectacles, either alone or in conjunction with other devices, sometimes serves to improve vision by excluding extraneous light from the sides.  Side shields are shown on the Stenopeic Spectacles, which are regularly made this way.  The shields work especially well in early cataract cases.  They will sometimes also remove the veiling glare of the retinal image resulting from corneal opacities.

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