lighting, aircraft, night vision imaging system - General Dynamics ...

MIL-STD-3009
APPENDIX A
measurement in order to assure that the photometer meets the requirements of this
document. Records of calibrations and checks shall be maintained by the contractor
and shall be available for Government inspection.
A.4.2 Photometer calibration.
The photometer shall be calibrated using methods that are traceable to NIST
standards.
A.4.2.1 Photometer sensitivity.
The full-scale sensitivity shall be 3.43 cd/m 2 (1.0 fL) or less, with a spot size of no
greater than 0.18 mm (0.007 inch).
A.4.2.2 Photometer accuracy.
The measured luminance of a NIST traceable luminance standard shall be within ±2%
of the NIST certified luminance.
A.4.2.3 Photometer sensitivity and accuracy verification.
The full-scale sensitivity and accuracy of the photometer shall be verified using a NIST
traceable standard of luminance set to a luminance value less than or equal to 3.43
cd/m 2 (1.0 fL) and also equal to the known full-scale sensitivity value of one of the
photometer ranges. Using a spot size no greater than 0.18 mm (0.007 inch) the
photometer full-scale sensitivity shall be within ±2% of the NTIS traceable standard of
luminance value.
A.4.3 Readout resolution.
The unit shall have a digital readout with a resolution better than or equal to 0.1% of full
scale.
A.4.4 Photometer optics.
The optics shall be capable of allowing measurements of spot sizes down to 0.18 mm
(0.007 inch) while meeting the sensitivity requirements of A.4.2.1. The optics shall be
capable of focusing to within 10 cm (4.0 inches).
A.4.5 Photometer viewing system.
The viewing system must be capable of locating the spot to be measured with a
maximum error of 0.05 mm (0.002 inch).
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