| Nicol | William, Scottish physicist, 1768-1851. See: Nicol prism. (05 Mar 2000) |
|---|---|
| Nicol prism | <physics> A prism, used for polarizing or analysing light, made by cementing together, with Canada balsam, two pieces of calcite in such a way that the extraordinary ray from the first piece passes through the second piece while the ordinary ray is reflected to the side into an absorbing layer of black paint. When two Nicol prisms are crossed, therefore, no light passes through. A polarizing prism made of two pieces of calcite specially cut, ground, polished and cemented. A transmitted beam splits into two polarized components, one of which is refracted into and absorbed by the asphalt mount. The remaining polarized beam is transmitted. Modifications of this prism are common. The Nicol prism (nicol) has generally been superseded by a polarizing film such as Polaroid. See: polars, polarizer, analyser. (05 Aug 1998) |
| accessory organs of the eye | The eyelids, with lashes and eyebrows, lacrimal apparatus, conjunctival sac, and extrinsic muscles of the eyeball. Synonym: organa oculi accessoria, accessory organs, accessory visual apparatus, adnexa oculi, appendages of eye. (05 Mar 2000) |
| accommodation of eye | The increase in thickness and convexity of the eye's lens in order to focus the image of an external object upon the retina. (05 Mar 2000) |
| amaurotic cat's eye | A yellow reflex from the pupil in cases of retinoblastoma or pseudoglioma. (05 Mar 2000) |
| anterior chamber of eye | The space between the cornea anteriorly and the iris/pupil posteriorly, filled with a watery fluid (aqueous humor) and communicating through the pupil with the posterior chamber. Synonym: camera anterior bulbi, camera oculi anterior, camera oculi major. (05 Mar 2000) |
| anterior eye segment | That part of the eyeball anterior to the lens. (12 Dec 1998) |
| antibiotic eye drops | <pharmacology> A medication that is pH balanced to allow placement into the eye for the purpose of killing bacteria. Examples include: Bleph-10, Chloromycetin, Cortisporin-Ophthalmic, Gantrisin, Genoptic, Gentacidin, Garamycin, Gantrisin, Ilotycin, Sodium Sulamyd and Sulphair. (27 Sep 1997) |
| aphakic eye | The eye from which the lens is absent. (05 Mar 2000) |
| appendages of eye | The eyelids, with lashes and eyebrows, lacrimal apparatus, conjunctival sac, and extrinsic muscles of the eyeball. Synonym: organa oculi accessoria, accessory organs, accessory visual apparatus, adnexa oculi, appendages of eye. (05 Mar 2000) |
| artificial eye | A curved disk of opaque glass or plastic, containing an imitation iris and pupil in the centre, inserted beneath the eyelids and supported by the orbital contents after evisceration or enucleation; it may be ready-made (stock) or custom-made. (05 Mar 2000) |
| bird's-eye | <botany> A plant with a small bright flower, as the Adonis or pheasant's eye, the mealy primrose (Primula farinosa), and species of Veronica, Geranium, etc. Source: Websters Dictionary (01 Mar 1998) |
| black eye | Ecchymosis of the lids and their surroundings. (05 Mar 2000) |
| bleary eye | Sore, runny, watery eye with an associated lackluster appearance and, by extension, dimness of vision. (05 Mar 2000) |
| blue-eye | <zoology> The blue-cheeked honeysucker of Australia. Source: Websters Dictionary (01 Mar 1998) |