US PATENT SUBCLASS 250 / 229
.~.~ Light valve (e.g., iris diaphragm)

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


250 /   HD   RADIANT ENERGY

200  DF  PHOTOCELLS; CIRCUITS AND APPARATUS {11}
216  DF  .~ Optical or pre-photocell system {11}
229.~.~ Light valve (e.g., iris diaphragm) {3}
231.1  DF  .~.~.~> Actuated by dynamic external physical quantity {4}
230  DF  .~.~.~> Reflection type(e.g., mirror galvanometer)
232  DF  .~.~.~> Light chopper type {1}

DEFINITION

Classification: 250/229

(under subclass 216) Subject matter having means in the optical path between light source and photocell for varying the amount of light which reaches the photocell.

(1) Note. In this subclass, the means for varying the amount of light which reaches the photocell is always a part of, or is continuously associated with, the photocell device, and is not an object which has an independent existence of its own. Devices found in this and indented subclass comprises, for example, keyboard operated shutters which variably permit a light source to illuminate a photocell, iris diaphragms and optical wedges.

SEE OR SEARCH THIS CLASS, SUBCLASS:

221+, for similar subject matter in which the light path between light source and photocell is directly affected by an object which is not part of the photocell apparatus and has an independent existence of its own.

237, for similar subject matter comprising relatively stationary hoods, gratings, baffles or diaphragms.