- an instrument that measures luminous intensity or brightness, luminous flux, light distribution, color, etc., usually by comparing the light emitted by two sources, one source having certain specified standard characteristics.
Origin of photometer
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Examples from the Web for photometer
An application of the law of intensity is made in using a simple (Bunsen) photometer.Physics
Willis Eugene Tower
The photometer or instrument for accurate comparison of lights, their amount and intensity, tells a different story.Astronomy
A valve is then fitted to one of the front openings, so that the light in that half of the photometer may be gradually diminished.A Color Notation
Albert H. Munsell
There is no other way of measuring the exposure than by the photometer or personal experience, and the latter is by far the best.
A number of measurements of the illuminating power of an electric lamp were rapidly made during the lecture with this photometer.
- an instrument used in photometry, usually one that compares the illumination produced by a particular light source with that produced by a standard sourceSee also spectrophotometer
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