Autofocus Reflecting. Projector? 
This new portable projector (Figure 17) 
was developed jointly by the Geological 
Survey and Reed Research, Inc., of Wash- 
ington, D. C. It can accommodate any 7 by 
7 inch portion of copy as large as 18 by 24 
inches having to be enlarged or reduced. 
The range of the instrument is from 1 to 
1.8 enlargement to a 3 to 1 reduction. An 
adaptor can be used to extend the range 
from 1 to 2 enlargement and from 2 to 1 
reduction 
Automatic focus is provided by a me- 
chanical Peaucellier linkage, shown in 
Figure 17, which provides the geometrical 
relation between the projector lens and 
the image and object planes. The instru- 
ment is light and readily portable, having 
a total weight of 58 pounds. 
U. S. PATENTS ISSUED TO GEOLOGICAL SUR- 
VEY PHOTOGRAMMETRISTS 
J. L. Buckmaster 
No. 2,342,640, Optical transfer in- 
strument, Feb. 29, 1944. 
No. 2,352,614, Transfer methods and 
instruments. 
No. 2,370,143, Camera lucida instru- 
ment and prismatic units therefor. 
H. T. Kelsh 
No. 2,341,031, Map making and pro- 
jection instrument. Oct. 12, 1948. 
No. 2,492,870, Stereoscopic projection 
map-making instrument, Dec. 27, 
1949. 
No. 2,522,975, Photogrammetric pro- 
jection machine, May 15, 1951. 
David Landen 
No. 2,487,814, Mapping instrument 
(topoangulator) Nov. 15, 1949. 
J. G. Lewis 
No. 2,321,033, Rectoblique plotter, 
June 8, 1943. 
No. 2,364,082, Map making from ae- 
rial photographs (photoangulator), 
Dec. 5, 1944. 
No. 2,561,386, Stereoblique plotter, 
July.24, 1951. 
R. M. Wilson 
No. 2,261,201, Photoalidade, Nov. 4, 
1951. 
U. S. PATENT APPLICATIONS 
R. K. Bean 
Twinplex stereoplotting instrument. 
Ellipsoidal-reflector projector. 
12 HISTORY OF PHOTOGRAMMETRY IN THE UNITED STATES 
  
Frc. 17. Autofocus reflecting projector. 
BIBLIOGRAPHY 
1. 
Wright, C. W., “The Panoramic Camera 
Applied to Phototopographic Work.” Am. 
Inst. of Min. Eng. Trans., Vol. 38, pp. 482- 
407, 1908. 
. Bagley, J. W., “The Use of the Panoramic 
Camera in Topographic Surveying,” U. S. 
Geol. Survey Bulletin 657, 1917. 
. Committee on Photographic Surveying of 
the Board of Surveys and Maps of the Fed- 
eral Government, “The Use of Aerial 
Photographs in Topographic Mapping,” 
Air Service Information Circular (Avia- 
tion), Vol. II, No. 184, March 10, 1921. 
.'Hacquinius, Eric and Shuster, E. A., Jr., 
"Construction and Operation of the 
Hugershoff Aerocartograph," U. S. Geol. 
Survey, Washington, 1929. 
. Birdseye, C. H., ‘Stereoscopic Phototopo- 
graphic Mapping,” Assoc. of Am. Geog- 
raphers Annals, March 1940, Vol. 30, no. 
1, pp. 1-24. 
. Birdseye, C. H., “Topographic Instructions 
of the U. S. Geological Survey,” U.S. Geol. 
Survey Bulletin 788, 1928. 
. Sargent, R. H. and Moffitt, F. H., "Aerial 
Photographic Surveys in Southeastern 
Alaska,” U. S. Geol. Survey Bulletin 797-E, 
1929. 
. Pendleton, T. P., “The Multiplex Stretches 
the Survey Dollar,” Civil Engineering, vol. 
9, no. 7, July 1939, pp. 401-404. 
. Arnold, H. H. and FitzGerald, Gerald, 
“Presentation and Acceptance of the Pho- 
togrammetric Award,” PHOTOGRAMMETRIC 
  
    
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
   
  
  
  
  
  
  
   
  
  
   
  
  
  
   
   
   
   
   
  
   
    
    
    
   
   
  
  
  
    
   
  
   
   
  
  
  
   
    
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