Jadak Photo Research SpectraScan PR-7 Series, Руководство пользователя

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Chapter 10
– Luminous / Radiant Intensity
100
H
OW TO
M
AKE
L
UMINOUS
I
NTENSITY
/ R
ADIANT
I
NTENSITY
M
EASUREMENTS
D
ESCRIPTION
The LR-730 LED Receptor enables the PR-7XX to measure the axial spectral radiant intensity (watts/steradian),
luminous intensity (millicandelas), and color of light emitting diodes (LED's).
The LR-730 consists of a 2.5 inch (63.5 mm) long tube with an LED port on one end and a mounting thread at
the other end. The threaded end is installed into the lens mount of the PR-7XX.
During use, the LED's are inserted into the LED port at the open end of the accessory. Two different sized LED
ports are supplied with the
LR-730 . One is designed to accept 0.118" (2.99 mm) diameter LED's, and the other
accepts 0.205" (5.21 mm) diameter LED's.
Note: Special adapters can be fabricated for LED's that do not exceed 0.275" (7 mm) in
diameter. Contact Photo Research for details.
G
EOMETRICAL
C
ONSIDERATIONS
The LR-730 is designed to measure the emittance of LED's over an 8.3

acceptance cone.
It is important to note that since the intensity distribution of LED's varies with angle, LED's measured using
acceptance cones other than 8.3

will produce different results. Generally, measurements through smaller cones
will yield higher values, while LED's sampled over larger cones will produce measurements with lower radiant
and luminous intensity values. Therefore, as part of the measurement report, it is important to note the
acceptance cone sampled during the test.
P
ROCEDURE
- LED A
DAPTER
C
AP
R
EPLACEMENT
If it becomes desirable to switch LED Adapter caps supplied with the LR-730 , proceed as follows:
1. Loosen and remove the two SAE 4-40 hex cap screws that secure the LED Adapter cap to the main
tube.
2. Remove the LED Adapter cap.
3. Insert the new adapter cap making sure to align the threaded holes in the adapter with the through holes
in the tube.
4. Replace and tighten the screws. DO NOT OVER TIGHTEN THE SCREWS!!
M
AKING
M
EASUREMENTS
1. Remove the MS-75 lens or other accessory by turning counter clockwise.
2. Install the LR-730 by threading it clockwise into the PR-7XX lens mount. Do not over tighten.
3. From the Instrument Setup menu, select LR-730
from the Primary Accessory window by touching the ▲
or
▼ icons.
4. Insert the LED into the adapter port and allow at least a 5 minute warm-up (unless otherwise specified).
5. Make sure the LED is properly seated in the adapter.
6. Touch the MEASURE button to begin a measurement.