IMPROVED SCREEN FOR REAR PROJECTION VIEWERS

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP79B00873A002000010008-4
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 4
• Document Creation Date: December 28, 2016
• Document Release Date: November 8, 2012
• Sequence Number: 8
• Publication Date: December 14, 1965
• Content Type: REPORT

Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873A002000010008-4 r
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CORNING GLASS WORKS
ELECTRO-OPTICS LABORATORY
RALEIGH, NORTH CAROLINA
Technical Report No.
Date - December 14, 1965
Period Covered - November 15, 1965
to
December 15, 1965
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Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873A002000010008-4
 Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873AO02000010008-4
Technical Report #5
C
This period saw the conclusion of the first phase of this
program which was devoted to a literature search of the open
and patent literature on rear projection screens and related
topics. The results of this were reported along with some
preliminary investigations in Technical Report #4'. We also
started the second phase of the program concerned primarily
with theoretical investigations, but also with instrumentation
and preliminary investigations of CGW materials.
A theoretical investigation of Rayleigh scattering
materials was begun, aimed at determining the feasibility
of using materials with Rayleigh scatterers as rear
projection screens. Rayleigh scattering theory was
first considered and the general scattering function
was developed. Separate terms in the scattering
function were then considered individually and
numerically evaluated to better understand how they
contribute to the scattering function. The most
important terms are
a. Dependence on the Refractive index of the Particles
Relative to the Supporting Matrix
b. Wavelength Dependence
c. Angular Dependence
d. Polarization Considerations
rWe have been able to show theoretically that it is not
possible, using only single scattering, to produce
%rear projection screens with satisfactory color
(characteristics. It appears as though only multiple
(Rayleigh scattering can significantly improve the color
(fidelity of these materials. The details of multiple
Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873AO02000010008-4
 Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873AO02000010008-4
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scattering are by far more complex than single
scattering theory but they will be considered in
detail along with other associated problems such
as overall efficiency and the influence of screen
thickness and the scattering function on resolution.
2. Investigations of Corning Glass Works Materials
C,
C
During this period we have received samples of
porous Vicor brand g1ass(l) from our facilities
in Corning, New York. These have been treated
to fill the open spaces, produced in the glass by
leaching, with varying concentrations of two
different opalizing agents. These are being
investigated to determine the influence of the
opalizing agents on the scattering properties of
the glass and to give a better understanding of
the basic limits of this type of material. We
also expect to have electron microscope data on
the size of the particles in these samples by
next period.
b. Reflective Coating of Hollow Fibers
We are continuing to investigate how to apply
highly reflective coatings on the inside and
outside of hollow fibers. Preliminary results
of our initial work are also expected next period.
Several different techniques are being considered
and are being checked on a small scale using
realistically sized fibers.
In connection with this we are requesting samples
of hollow fiber matrices. We will investigate
techniques to put a reflective coating in these
fibers and subsequently determine their optical
properties.
"Improved Screen for Rear Projection Viewers",
Technical Report No. 4, November 5, 1965.
Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873AO02000010008-4
 Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873AO02000010008-4
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3. Instrumentation
a. Goniophotometer
Design of a goniophotometer was begun. The optical
design has been completed and components are on
order. Design work on the remainder of the instrument
will be concluded next period with construct-ion
occupying all of the following period.
b. Modulation Transfer Function Analyzer
Design of a modulation transfer function analyzer
which will be used to determine screen resolution
will start next period. It will be specially designed
taking into consideration the unique characteristics
of rear projection screens. It will allow resolution
measurements for other than on axis viewing and
duplicate as nearly as possible a rear projection
system.
Declassified in Part - Sanitized Copy Approved for Release 2012/11/08: CIA-RDP79B00873AO02000010008-4