Specifications

MIL-STD-1472E
5.11 .3.12.4 Uniformity. Sights shall be evenly illuminated by means of an opal diffuser or
similar device.
5.11 .3.12.5 Reticle lines. The thickness of reticle lines for illuminated sights should be not less
than 150 rnrad (0.5 rein) visual angle. They shall be thin enough so as not to obscure targets, but thick
enough to be easily seen. In any case, their thickness should not exceed 600 rnrad (2 rein).
5.11.3.13 Binoculars/bioculars.
5.11 .3.13.1 Biocular viewing. Where continuous use of a sight under low levels of
illumination will exceed one minute, the single optical train shall be provided with two eyepieces if this
does not lead to unacceptable light losses.
5.11 .3.13.2 Eyepiece separation. Binoculrdbiocular instruments should have an eyepiece
separation scaled from 50 to 73 mm with 1 mm interval markings.
5.11 .3.13.3 Ramification differences. Magnification differences of the two barrels should not
exceed 2%.
5.11 .3.13.4 Luminous transmission differences. Luminous transmission differences of the two
barrels should not exceed 5%.
5.11 .3.13.5 Matched oculars. To avoid size differences in the images presented to the two eyes
(that may induce eyestrain or headache), oculars shall be matched in focal length, i.e., shall be matched
pairs.
5.11 .3.13.6 Weight. The weight of handheld binocularshioculars shall be not greater than 1.5
kg (3.3 pounds) and should be not greater than 1 kg (2.2 pounds).
5,11.3.14 EYtxuPs and headrests. Any optical instrument requiring steady orientation of the
eyes shall be provided with a headrest or eyecups, or both.
5.11 .3.14.1 EYecuPs. Eyecups shall be provided to maintain proper eye relief, eliminate stray
light and, when mquirml, protector cushion the eyes and orbital region against impact with the
eyepieces. The radii of Figu~ 49 define a surface of revolution within which a satisfactory
symmetrical eyepiece and cup must be designed if interfemwes with facial features am to be avoided.
These should be applied [o cushion forms when they are compressed to the maximum.
5.11 .3,14.2 Headrests/brow pads. A headrest or brow pad shall be used to absorb energy
which would be injurious to the operator’s head.
5.11 .3.14.3 ComPatibili~ with clothing and personal euuipme
nt. Eyecups and headrests shall
be compatible with helmets, protective masks, and other clothing and personal equipment.
5.11.3.15 Accessories.
5.11.3 .15,1 Filters:
5.1 I.3.15.1.1 General. Light filters, removable from the oplical path, should bc provldcd [o
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