SPECTRA

ELECTRO-OPTICAL INSTRUMENTS AND DEVICES FOR MEASURING RADIANT ENERGY IN SCIENTIFIC, INDUSTRIAL, AND PHOTOGRAPHIC APPLICATIONS-NAMELY, COLOR TEMPERATURE METERS, EXPOSURE METERS, DENSITOMETERS, COLOR DENSITOMETERS, METER TESTING EQUIPMENT, LIGHT FILTERS, VIEWING GLASSES; INSTRUMENTS FOR PHOTOMETRY AND RADIOMETRY-NAMELY, LUMINANCE METERS, RADIANCE METERS, ILLUMINANCE METERS, IRRADIANCE METERS, SPECTRORADIOMETERS, CANDLE-POWER METERS, OPTICAL LENSES, CONTROL CONSOLE UNITS, POWER SUPPLY UNITS, DISABILITY GLARE INTEGRATORS, PHOTOMETRIC TESTING EQUIPMENT, TRIPODS, OPTICAL HEADS, HIGH RESOLUTION IMAGE PROJECTORS, LENS CALIBRATING DEVICES, BRIGHTNESS RESPONSE METERS, REFLECTANCE STANDARDS, LUMINANCE STANDARDS, AND MONOCHROMATIC LIGHT SOURCES