INCH-POUND MIL-PRF-13830B MIL-O-13830A 1].pdf · PDF fileINCH-POUND MIL-PRF-13830B 9...

Click here to load reader

  • date post

  • Category


  • view

  • download


Embed Size (px)

Transcript of INCH-POUND MIL-PRF-13830B MIL-O-13830A 1].pdf · PDF fileINCH-POUND MIL-PRF-13830B 9...


    MIL-PRF-13830B9 January 1997SUPERSEDINGMIL-O-13830A11 September 1963


    Beneficial comments (recommendations, additions, deletions) and anypertinent data which may be of use in improving this document, should beaddressed to: Commander, U.S. Army ARDEC, ATTN: AMSTA-AR-EDE-S,Picatinny Arsenal, New Jersey 07806-5000 by using the StandardizationDocument Improvement Proposal (DD Form 1426) appearing at the end of thisdocument or by letter.

    AMSC N/A FSC 6650

    DISTRIBUTION STATEMENT A. Approved for public release; distribution isunlimited.


    This specification is approved for use by all Departments and Agencies of theDepartment of Defense.

    1. SCOPE

    1.1 Scope. This specification covers the manufacture, assembly, andinspection of finished optical components such as lenses, prisms, mirrors,reticles, windows and wedges for fire control instruments.


    2.1 General. The documents listed in this section are needed to meet therequirements specified in sections 3, 4, and 5 of this specification. This sectiondoes not include documents in other sections of this specification orrecommended for additional information or as examples. While every effort hasbeen made to ensure the completeness of this list, document users arecautioned that they must meet all requirements documents cited in sections 3,4, and 5 of this specification, whether or not they are listed.

  • MIL-PRF-13830B


    2.2 Other Government documents, drawings, and publications. Thefollowing other Government documents, drawings, and publications form a partof this document to the extent specified herein. Unless otherwise specified, theissues are those cited in the solicitation.



    C7641866 - Surface Quality Standards for OpticalElements

    (Copies of other Government documents, drawings, and publications requiredby contractors in connection with specific acquisition functions should beobtained from the contracting activity or as directed by the contracting activity.)

    2.3 Order of precedence. In the event of a conflict between the text of thisdocument and the references cited herein, the text of this document takesprecedence. Nothing in this document, however, supersedes applicable lawsand regulations unless a specific exemption has been obtained. (See contractprovisions for additional precedence criteria.) 3. REQUIREMENTS

    3.1 General. All optical elements, components and systems shall complywith the requirements of this specification, except as further defined in thedetailed instrument specification or on applicable drawings forming a part of thecontract.

    3.2 Materials. Materials shall be in accordance with applicablespecifications or component or instrument drawings.

    3.2.1 Glass, optical. Optical glass shall be of type and grade specified onthe drawings. On authorization to use glass other than that specified, completeinformation regarding the optical characteristics of the glass and design datashall be furnished to the contracting officer. Radioactive material. Optical glass specified herein shall contain nothorium or other added radioactive materiel in excess of 0.05 percent by weight.

    3.2.2 Adhesive. Unless specified by the contract or order, optical cementshall be in accordance with Appendix A.

  • MIL-PRF-13830B


    3.2.3 Bonding system. Bonding system for glass to metal bonding shall bein accordance with Appendix D.

    3.2.4 Sealing compound. Sealing compound shall be in accordance withAppendix E.

    3.2.5 Reflection reducing film. Reflection reducing film required for coatingof specified optical surfaces shall be in accordance with Appendix C. Reflecting surfaces . Aluminized reflecting surfaces shall be inaccordance with Appendix B.

    3.3 Mechanical dimensions. Optical elements shall conform to themechanical dimensions and optical data specified on the drawings or in thecontract.

    3.3.1 Rim edges. Rim edges of all optical parts shall have a chamfer of0.020 inch - 0.010 at 45 degrees 15 degrees as measured along the face widthunless otherwise specified by the drawing. Edges meeting at angles of 135degrees and larger need not be beveled unless specified by the drawings.

    3.4 Finish and defects. Finish and defects of the optical glass shall conformwith requirements of this specification or as indicated on applicable drawings oroptical diagrams.

    3.4.1 Glass defects. Striae, cords, ream, bubbles, seeds, strain, laps, foldsin pressings, or any other defect located in such a point, plane, or position as toimpair the performance of the element shall be cause for rejection of thatelement.

    3.5 Optical glass surface quality.

    3.5.1 Optical drawings and diagrams. Component optical drawings shallindicate surface quality, and optical system diagrams shall indicate thediameter of an axial beam of rays. Designation of defect size. Limiting sizes of surface defects shall bedesignated on the drawings by two numbers which refer to two graded sets ofsurface quality standards per Drawing C7641866. The first number shall referto scratches and the second number shall refer to digs (see 6.3).

    3.5.2 Scratches. Circular element. The combined length of maximum size scratches

  • MIL-PRF-13830B


    located on each surface of an optical element shall not exceed one quarter thediameter of that element. Maximum combined lengths of scratches. When a maximum sizescratch is present, the sum of the products of the scratch numbers times theratio of their length to the diameter of the element or appropriate zone shall notexceed one half the maximum scratch number. When a maximum size scratchis not present, the sum of the products of the scratch numbers times the ratioof their length to the diameter of the element or appropriate zone shall notexceed the maximum scratch number. Noncircular shaped element. The computing diameter of elementshapes other than circular shall be that of a circle of equal area. Scratchesbeyond the free aperature of any element as given on the optical systemdrawings or detail drawings shall not be considered when applying theappropriate formula specified in True roof surfaces on prisms. True roof surfaces on prisms shallbe considered equivalent to a single surface equal to the sum of the individualroof areas for purposes of scratch and dig computation, except that the roofedge shall not be considered in the summation of the length of the allowablescratches. Scratch and dig tolerances for roof prisms are set on the basis thatthe equivalent surface above is viewed from the air side. ( Surface quality, central zone. Areas of surfaces whose specifiedscratch qualities are 20 or better shall have no more than 4 separate scratchesin any 1/4-inch diameter circular area. This requirement does not apply forscratches smaller than number 10. Surface quality, outer zone. Surface quality outside the freeaperture of any element shall be considered 80-50, unless otherwise required. Coating scratches. Coating scratches, scratches which do notpenetrate the glass surface, shall be within the same limits specified in 3.5.2. Coating scratches shall be considered separate from the substrate scratchrequirements.

    3.5.3 Digs. Dig designation. Dig numbers are the actual diameters of defectsallowed, specified in units of 1/100mm. In the case of irregular shaped digs thediameter shall be taken as the average of the maximum length and maximumwidth.

  • MIL-PRF-13830B

    5 Maximum size digs. The permissible number of maximum size digsshall be one per each 20mm of diameter or fraction thereof on any single opticalsurface. The sum of the diameters of all digs as estimated by the inspectorshall not exceed twice the diameter of the maximum size specified per 20mmdiameter. Digs less than 2.5 microns shall be ignored. Surface quality. All digs on each surface whose dig quality isnumber 10 or smaller shall be separated edge to edge by at least 1mm. Themeasurement of scattering shall not be required for surfaces where digs largerthan number 10 are allowed.

    3.5.4 Bubbles and inclusions. Bubbles shall be classed as surface digs. Any inclusion in the glass shall be treated as a bubble. The size of irregularshaped inclusions shall be considered as one half the sum of the maximumlength and the maximum width. Bubble size tolerances are identical in allrespects to digs; but the bubble tolerance, is in addition to the dig tolerance. Maximum size bubbles. The permissible number of maximum sizebubbles shall be one per 20mm of light path, or fraction thereof, of any singleelement. The sum of the diameters of all bubbles as estimated by the inspectorshall not exceed twice the diameter of the maximum size specified per 20mmdiameter for each 20mm of light path. When surface dig quality is 10 orsmaller, bubbles shall follow requirements for digs as specified in

    3.5.5 Limiting size of surface defects. If not specified on drawings, thelimiting size of scratches or digs shall be determined from Table I and is basedon the beam diameter of magnification. Beam diameter of magnification. The