Gain: Difference between revisions
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=== Conversion === | === Conversion === | ||
To convert between metric and imperial units, use the following formula: | To convert between metric and imperial units, use the following formula:<math display="block">\mathrm{G}_{\mathrm{fL} / \mathrm{fc}} = \mathrm{G}_{\mathrm{cd} / \mathrm{m}^2 / \mathrm{lx}} * \pi</math> | ||
<math>\mathrm{G}_{\mathrm{fL} / \mathrm{fc}} = \pi</math> | |||
== Notes == | == Notes == | ||
Revision as of 13:40, 28 March 2023
Gain, also called brightness gain or luminance gain, is the measurement of the increase in brightness between the input and the output of an image intensifier tube.
Specification
There are two different ways of specifying gain.
Imperial
Gain specified in imperial units uses the units of foot-Lamberts by foot-candle (Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\textstyle \mathrm{fL} / \mathrm{fc}} ).
Measurement
To measure gain in accordance to the MX-10160/AVS-6 specification, the photocathode is exposed to Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\textstyle 2 * 10^{-6} \mathrm{fc}} of input light. A photometer is then used to measure the luminance (brightness) of the phosphor screen (in Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\textstyle \mathrm{fL}} ). The resulting value is divided by Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\textstyle 2 * 10^{-6}} to obtain the gain in Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\textstyle \mathrm{fL} / \mathrm{fc}} .[1]
To further test auto brightness control, the same procedure is usually repeated with Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\textstyle 2 * 10^{-4} \mathrm{fc}} .
Manufacturers
The following manufacturers are known to use imperial units when specifying gain:
Metric
Gain specified in metric units uses the units of candela per square-meter per lux (Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathrm{cd} / \mathrm{m}^2 / \mathrm{lx}} ).
Manufacturers
The following manufacturers are known to use metric units when specifying gain:
Conversion
To convert between metric and imperial units, use the following formula:Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \mathrm{G}_{\mathrm{fL} / \mathrm{fc}} = \mathrm{G}_{\mathrm{cd} / \mathrm{m}^2 / \mathrm{lx}} * \pi}
Notes
- ↑ Photonis does sometimes use imperial units alongside metric units, especially when selling in the United States.
References
- ↑ http://everyspec.com/MIL-SPECS/MIL-SPECS-MIL-I/MIL-I-49428_53852/ (page 8, item 3.6.8)
