10X OBJECTIVE LENSES AS USED IN(SANITIZED) ,MICRO-ANALYZER

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78B04770A001400070017-3
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 3
• Document Creation Date: December 28, 2016
• Document Release Date: June 27, 2006
• Sequence Number: 17
• Publication Date: November 14, 1967
• Content Type: MF

Approved For Release 2006/06/27: CIA-RDP78B04770A001400070017-3
Approved For Release 2006/06/27: CIA-RDP78B04770A001400070017-3
 Approved For Release 2006/06/27: CIA-RDP78BO477OA001400070017-3
NPIC/TDS/E-44567
14 November 1967
DS/ESB
SUBJECT: lOX Objective Lenses as Used in
Micro-Analyzer
1. In respo the above mentioned lenses
were secured from of TID and were checked on
an optical bench to determine the spread of the focal plane
red, green, and blue. The lenses in question were standard
lOX objectives designed to be used without cover glass at a mm
tube length. The only apparent modification was the blackening of
all interior metal surfaces. In the Micro-Analyzer they are being
used at tube lengths of approximately 18 inches.
2. A check of the lenses with no cover glass at 18-inch tube
lengths indicated a spread in excess of 150p between green and blue
focus on the object plane, or 3mm in the image plane of the objec-
tives. When a cover glass approximating the thickness of the sup-
port plate for the film was used between the object plane and the
lens, this spread increased appreciably. The in-focus resolution
for each color was in excess of 900 lines/mm
3. When the lenses were tested at the correct tube length the
spread between colors was reduced to less than 5? in the object plane.
This figure is approaching the precision of the experiment. The
tolerance given on tube length for a lOX .25NA objective is f40mm
for a 160mm tube length for normal work (biological) and much less
than this for critical work.*
4. It is concluded that the focussing problem outlined above
(focus is a function of wave length) is strictly a matter of using
lenses in a mode for which they were not designed.
5. It is recommended that either the existing lenses be modi-
fied or new lenses.be designed for the appropriate tube length. It
is also suggested that the top lens be specified for use with no
cover glass as in the original specification, but at the correct tube'
length; however, the bottom lens should include.also the specification
that it is to be designed for viewing through a glass stage of the
appropriate thickness.
Rudolph Kingslake, Applied Optics and Optical Engineering, "?" ?'_W&
99 Vol. III, p. 160, Academic Press, New York, 1965 W 51'.1-3d Aac afte 4
DDR-DUPE 6"jJ f1
Approved For Release 2006/A PtIA-RDP78BO477OA001400070017-3
 Approved For Release 2006/06/27: CIA-RDP78BO477OA001400070017-3
SUBJECT: lOX Objective Lens as Used in
Micro-Analyzer
6. Two other courses are open; however, both have disadvan-
tages which may cause problems. The first is the use of an appro-
priately selected relay lens in both the illumination and the imaging
legs of the optical train. The two lenses would be different due
to the cover glass requirement. This would call for selection or
design of the appropriate lenses plus some mechanical modifications
to the Micro-Analyzer to mount them. The second course would be
to investigate the suitability of a lens such as the Mcro-Tessar
Photomicrographic lens in this application. Unfortuna e y, this
lens is only available with f4.5 aperture or approximately N.A. 0.1
which may not be adequate for the current application.
Distribution:
Original - Addressee
1 - Ch/DS TDS
1 - W. TID
2 - NPIC TDS EDL
C REt
Approved For Release 2006/06/27: CIA-RDP78BO477OA001400070017-3