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An affection of the eye, in which the patient perceives luminous rays, flashes, coruscations, etc. See phosphene.

Same as Photopsia.

A printing surface in relief, obtained by photographic means and subsequent manipulations. Knight.

Anything employed for the observation of light or luminous effects.

Of or pertaining to the photoscope or its uses.

A process in which, by means of a number of photographs simultaneously taken from different points of view on the same level, rough models of the figure or bust of a person or animal may be made with great expedition.

A sphere of light; esp., the luminous envelope of the sun.

Of or pertaining to the photosphere.

ich appears in the cells almost simultaneously with the sugars. The chloroplasts perform photosynthesis only in light and within a certain range of temperature, varying according to climate. This is the only way in which a plant is able to organize carbohydrates. All plants without a chlorophyll apparatus, as the fungi…

er such influence. If the migration is toward the source of light, it is termed positive phototaxis; if away from the light, negative phototaxis. --Pho`to*tac"tic (#), a. --Pho`to*tac"tic*al*ly, adv.

Telegraphy by means of light, as by the heliograph or the photophone. Also, less properly, telephotography. -- Pho`to*tel"e*graph (#), n. --Pho`to*tel`e*graph"ic (#), a.

A telescope adapted for taking photographs of the heavenly bodies.

An arrangement of two photographic cameras, the plates of which may be brought into exactly the same plane, used in surveying and map making. From the differences between two pictures taken at the same moment, measurements in all dimensions of the region may be obtained.

The application of light for therapeutic purposes, esp. for treating diseases of the skin. -- Pho`to*the*rap"ic (#), Pho`to*ther`a*peu"tic (#), a.

Of or pertaining to both light and heat.

A motile condition in plants resulting from exposure to light. -- Pho`to*ton"ic, a.

Photogrammetry. -- Pho`to*top`o*graph"ic (#), Pho`to*top`o*graph"ic*al (#), a.

Designating a photomechanical process for making reproductions in natural colors by three printings.

Same as Heliotropic.

The tendency of growing plant organs to move or curve under the influence of light. In ordinary use the term is practically synonymous with heliotropism.