(under subclass 46) Subject matter including a telescope for passing unknown visible radiation and having an objective and ocular lens system, and means to locate, physically or optically, the incandescent standard in the optical path of the lens system so that visible radiation of the standard and the unknown radiation may be viewed simultaneously.
(1) Note. Herein are those telescopic pyrometers which attenuate the intensity of the light or the color of the unknown source or the standard by optical means.
SEE OR SEARCH THIS CLASS, SUBCLASS:
46, for calibrated light standard systems, per se, used for comparison with unknown visible light for temperature, colorimetry or photometry purposes.
230, for photometers which visually compare light intensities by means of an incandescent standard.
364+, for tests which utilize polarized light for examination purposes where temperature is not involved.
404, for color or shade determination for photos:graphic purposes where color temperature is not involved. 416+, for shade or color tests involving optical filters where temperature is not involved.
417, for flame detecting photometers not concerned with temperature which utilize color filters rather than dispersing or diffracting elements to separate the radiation into discrete colors.
425, for color determination by light intensity comparison where color temperature is not involved.
SEE OR SEARCH CLASS
359, Optics: Systems (Including Communication) and Elements,
738, for lens systems having light limiting or controlling means.
