(under the class definition) Subject matter including means to heat, cool, reduce the rise in temperature, or ventilate all or part of the projection system or the picture to be projected.
SEE OR SEARCH THIS CLASS, SUBCLASS:
4, for slide changing by rising heated air.
SEE OR SEARCH CLASS
352, Optics: Motion Pictures,
143+, and 202 for fire preventing, ventilating and cooling a motion-picture projector. 355, Photocopying,
30, for a projector printer having temperature control.
362, Illumination,
293, for such structure having a heat filter and subclass 294 for light-projection structure having ventilating and cooling means. See the note to Class 362 below the class definitions to this Class 353.
399, Electrophotography,
9+, for diagnostics and subclasses 38+ for controls.
