Jadak Photo Research SpectraScan PR-7 Series, Руководство пользователя

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Chapter 8
– How to Make a Luminance / Radiance Measurement
92
U
SING THE
LA-730 L
UMINANCE
A
DAPTOR
FIGURE 78 - LA-730 LUMINANCE ADAPTOR
The Luminance Adaptor enables the PR-7XX to measure surface luminance and radiance of backlit sources
(e.g. cathode ray tubes, fluorescent lamps and self-luminous displays) that can be placed in contact with the
rubber cup of the Adaptor. It can also be used to approximate the luminance of more distant sources, averaged
over a circular field. (The acceptance angle of the adaptor is approximately 12.5

at the half-power points and
14

at the 10% response points. The measuring area is 0.52 inch (13.2 mm) in diameter when the cup of the
accessory is placed in contact with a Lambertian source. It features an ambient light shield which eliminates
room lighting from affecting the measurement.
Warning: The LA-730 is not recommended for use when measuring LCDs as the act of
coming in contact with the device may distort the surface and yield erroneous
readings and may cause damage to the display.
1. Remove the MS-75 Objective lens or other accessory by turning it counterclockwise.
2. Install the Luminance Adaptor by screwing in clockwise. Do not over-tighten!
3. From the Instrument Setup
menu, touch the ▲ ▼ icons adjacent to
Primary Accessory until
LA-730 appears.
4. Make any other changes such as Aperture , Sensitivity, Speed, Average etc.
5. Place the front surface of the rubber cup of the Luminance Adaptor in contact with the target. Make sure
it is within the lit area or the device.
6. Touch the MEASURE button to begin a measurement.