Quantcast Inspecting Optical Components

Order this information in Print

Order this information on CD-ROM

Download in PDF Format

     

Click here to make tpub.com your Home Page

Page Title: Inspecting Optical Components
Back | Up | Next

Click here for a printable version

Google


Web
www.tpub.com

Home


   
Information Categories
.... Administration
Advancement
Aerographer
Automotive
Aviation
Combat
Construction
Diving
Draftsman
Engineering
Electronics
Food and Cooking
Math
Medical
Music
Nuclear Fundamentals
Photography
Religion
USMC
   
Products
  Educational CD-ROM's
Printed Manuals
Downloadable Books
   

 

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Back
Figure 9-26.  Marking a Single Prism
Up
TM-9-254 Gearcase Transfer M548 M548A1 (
Next
Inspection Requirements
TM 9-254 9-5. Marking Optical Components - Continued c. Marking Components for Light Travel and Deviation.  The marking of components for light travel, deviation in prisms, and focal length in lenses is usually done by the manufacturer.  To help the repair person understand what these markings represent, a brief description is as follows: (1) Variations in lenses from the intended focal length represents the only characteristic usually noted on a lens.  The lens should be marked on its unpolished surface in a plus or minus thousandths of an inch, according  to  whether  its  focal  length  is  longer  or  shorter  than  that  desired  or  specified,  as  shown  in figure 9-25. (2) In prisms, such as binocular prisms, the direction of deviation is indicated such as 2 o’clock, 5 o’clock, or 6 o’clock, followed by the amount of deviation such as 2 minutes, 3 minutes, or 4 minutes.  For example a prism marked 5-3 indicates that the prism has a 3 minute deviation at 5 o’clock.  Light travel, whatever the method used for its determination should be noted as plus or minus in relation to the ideal condition, and should be marked in thousandths of an inch such as .007 or .005 on the prism as shown in figure 9- 27. 9-6. Inspecting Optical Components. a. General Inspection.  All optical components should be inspected by the repair- person for defects before they are  installed  in  an  optical  system.    All  components  will  be  inspected  according  to  the  criteria  contained  herein.    Any component  not  meeting  these  standards  must  be  reground  and  repolished.    Should  the  defects  of  the  component  be extensive, the component should be discarded. b. Definitions of Defects: (1) Chip.    An  indentation,  usually  irregular  in  shape,  in  a  glass  surface  where  a  small  piece  of  the  glass surface has been chipped out, struck, or flaked off.  A small crack which can be removed by honing. (2) Condensation (Moisture).  Visible particles of water or visible staining due to the presence of water on the component. (3) Dig.    A  small,  very  short  scratch  in  the  glass  surface.    The  size  of  the  dig  can  be  measured  by comparison with the established dig standard. (4) Dirt.  Visible particles or specks of foreign matter, such as dust, soil, paint flakes, and sand adhering to the glass surface. (5) Fingerprints.  A visible impression upon the glass surface of the arches, loops, whirls, or composites of the fingertip(s). (6) Fractures.    A  crack  or  break  on  the  exterior  of  the  component  and  extending  well  into  or  all  the  way through the glass diameter or thickness. (7) Inclusions.  A term used to denote the presence, within the body of the glass, of extraneous or foreign matter.  Bubbles, for example, are a gaseous inclusion. (8) Lint.    Particles  of  cloth  or  paper  fibers  adhering  to  the  component  surface  or  entrapped  between  the cemented component surfaces. Change 2  9-20

Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing

Integrated Publishing, Inc.