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发表于 2003-8-7 19:07:00
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美军标连载(Mil-Prf-13830B)
3.6.3 Bonding defects (glass to mental) Bonded optical assemblies shall have a continuous bead of the cured adhesive along the edge of the bonded surface.
3.6.3.1 Voids and separations Subsequent to meeting the requirements of 3.7.2 and 3.8.2.5.2, there shall be no voids or separations that exceed 10 percent of the bonded area.
3.7 Optical component details
3.7.1 Temperature operation Cemented components as a result of exposure to ambient air temperatures of minus 80±2 degrees and plus 160±2 degrees F shall not develop “feathering”, show evidence of separation or softening of cement or other defect, except as specified in 3.6, with the provision that the increase or development of edge separation or edge cement defects shall be cause for rejection.
3.7.2 Relative humidity-temperature operation Cemented components as a result of exposure to an ambient atmosphere of plus 130±2 degrees F temperature, and at least 95 percent minimum relative humidity, and subsequent exposure to ambient air temperature of minus 80±2 and plus 160±2 degrees F, shall not develop ‘feathering”, shall evidence of separation or softening of cement or other defects, except as specified in 3.6.
3.7.3 Reflection reducing films Optical surface specified on drawings as “surface to be coated” shall be coated with a reflection reducing film (see 3.2.5).
3.7.4 Optical blackening When specified, ground surfaces of optical elements shall be blackened with a finish approved by the responsible technical activity.
3.7.5 Resolution Resolution tests shall be performed on each objective, collective erector, eyepiece, mirror, wedge, window, filter, prism and prism assembly (optical) as specified in 4.2.5.
3.7.6 Parallelism, filters Parallelism of filters shall be within the tolerance specified on the drawings. When no tolerance is specified, filters located internally or in front of a telescope shall not exceed 1 minute of arc light deviation. Filters located between the eyelens and the exit pupil shall not have a light deviation exceeding 5 minutes of arc.
3.7.7 Reticle scale spacing Reticle scale spacing shall be tested in accordance with 4.2.10.5.
3.7.8 Polished surfaces Polished surfaces shall no evidence of grayness or stain when inspected in accordance with 4.2.2.
3.7.9 Lenses
3.7.9.1 Surface quality Surface quality of each lens shall be in accordance with applicable drawings or instrument specifications. When not specified, the surface quality shall be as following: Objectives, erectors, windows and other elements which lie at least fifteen diopters out of the focal plane, shall have a surface quality of 80-50 or better. Filed and collective lenses shall have a surface quality of 20-5 in the central zone and 40-15 in the outer zone. Center lenses of oculars shall have a surface quality of 40-15 in the central zone and 40-20 in the outer zone. Eyelenses, excepting those in symmetrical eyepieces, shall have a surface quality of 40-20 in the central zone and 60-30 in the outer zone. When the field and eyelens are identical, the surface quality for both shall be 20-5 in the central zone and 40-15 in the outer zone. Filters which lies between the eyelens and the exit pupil shall have a surface quality of 40-20 in the central zone and 60-30 in the outer zone. Filters which lie internally shall have the same requirements as specified for prisms in 3.7.10.1. Filters located in front of the objective shall have a surface quality of 80-50 or better.
3.7.9.2 Fractures and edges chips Edge chip which do not encroach on the free aperture of the lens shall be allowable, providing the chip does not interfere with the sealing of the lens in the mount. The surface of all chips larger than 1/2 mm, as measured at the largest extremities, shall be “stoned” to roughen it and lessen the possibility of annoying reflections and additional chipping. The sum of the chip widths of chips larger than 1/2mm, as measured at the edge of the lens, shall not exceed 30 percent of the perimeter. Fractures in any face or edge shall be ground out. Ground out areas shall remain within the applicable stoned chip limits of this paragraph. Stoned chips and fractures in ground faces whose total summed up areas are in excess of 2 percent of the area of the ground face or which are in excess of 2 mm depth shall be cause for rejection. Such stoned chips and fractures shall be cause for rejection when they interfere with the optical path, mounting or sealing methods regardless of their size.
3.7.9.3 Concentricity Edges of all elements shall be trued to diameter about the optical axis as a center by grinding. Lenses composed of two or more elements shall be cemented and centered in such a manner that the axis of each element coincides with the axis or axes of the other element or elements. Ocular lenses shall be concentric within 6 minutes of arc, and all other lenses shall be concentric within 3 minutes of arc unless otherwise specification on the drawing or in item specifications. After centering and cementing, mechanical eccentric glass overhang in excess of 50 percent diameter tolerance shall be removed. Optical eccentricity is defined as the angular deviation, after refraction of an incident ray which is coincident with the geometric axis of the lens.
3.7.10 Prisms and mirrors
3.7.10.1 Surface quality Surface quality of each prism shall be in accordance with applicable drawing or instrument specifications. For surfaces which lie at least 15 diopters out of the focal plane, quality shall be 80-50 or better. For surfaces which lie within 5 to 15 diopters of the focal plane the surface quality shall be 20-5 for the central zone and 40-15 for the outer zone. For surfaces which lie within 5 diopters of the focal plane surface quality shall be the same as for reticles.
3.7.10.2 Fractures and edge chips Edge chips which do not encroach on the free aperture of the prism shall be allowable within the following limitations: The sum of the chip widths shall not exceed 30 percent of the length of edge on which the chips occur. Chips shall be measured from the bevelling edge, not from sharp edge; i.e. after bevelling and not before. Chips less than 1/2 mm shall be stoned. Encroachment of chips shall be measured on the faces of the prism from the beveled edges. If the nominal length (measured to sharp corner before beveling) of the shortest edge of the prism which is adjacent to any polished face is an inch or less, chips may encroach the faces 1mm; if said length exceeds 25.4mm chips may encroach 2mm. This shall be permissible provided that there are no edge chips which interfere with mounting or sealing and the chips do not encroach upon the free aperture. Fractures visible to the unaided eye on any surface or edge are not permitted.
3.7.10.3 Drawing requirements The deviation of angle errors, pyramidal error or error due to pyramid, spherical power, astigmatism, resolution, and image tilt shall be as specified on the drawings.
3.7.10.4 Erecting prisms Erecting prisms shall be inspected as specified in 4.5.2.2.
3.7.10.5 Reflecting surfaces-silvered or aluminized
3.7.10.5.1 Edges The edges of partially silvered surfaces of ocular prisms shall be sharp and shall be free of irregularities when inspected with the aid of a magnifier of at least the power of eyepiece of the instrument to which the prism pertains.
3.7.10.5.2 Defects Defects on reflecting surfaces appear the same as defects on other optical surfaces and shall be treated in the same manner as specified in 3.7.10.1.
3.7.10.5.3 Aperture surfaces Aperture surfaces of prisms through which light is to be transmitted shall be free from particles of silver or aluminum retaining from processing of other surfaces.
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