It should be noted that the picture element size of the images 
which we produced as JERS-1 simulation stereoscopic images was 
18.3 m x 18.3 m. This means that we produced not raw images 
but geometrically corrected images because the picture element 
size'of the raw image is 18,3 m x 24.0 m at the nadir looking 
sensor image and about 19.1 m x 24.0 m at the forward looking 
sensor image. 
6. Lineament extraction experiment from JERS-1 stereoscopic 
images 
We carried out some experiments to investigate the usefulness 
of | JERS-1 stereoscopic images from the standpoint of 
the earth resources exploration. One of the results of these 
experiments is shown in Figure 4. The four maps are the 
results of lineament extraction from four stereoscopic images 
which differ in base-to-height (B/H) ratios. These 
stereoscopic images of different B/H ratios were made by 
changing the angle of the forward looking sensor at the 
developed image production system. These lineaments were 
drawn professionally using a stereoscope. Table 1 shows the 
total numbers and lengths of these lineaments in each map. 
From these results we can say as follows. 
  
(1) We can extract the maximum amount of lineaments from 0.5 
B/H ratio stereoscopic images, but 0.3 images are not very 
inferior to 0.5 images. 
(2) "The ^B/H 'ratio of 1.00 is too large. to ^ extract linea- 
ments in this area where the slope of the earth's surface is 
somewhat steep. 
(3) The |B/H- ratio of 0.1 is too small ‘to extract linea- 
ments even in this somewhat steep slope area. 
(4) We can extract many unknown lineaments from 0.3 
images, so it can be said that the stereoscopic images of 
JERS-1 are very useful to explore earth resources. 
Table 1 Total value of lineaments extracted from four 
stereoscopic images which differ in B/H ratios 
  
  
  
B/H ratio 
0.1 0.3 0.5 1.0 
Lineament 
Total number 135 284 330 262 
Total length (km) 305.86 594.13 730.10 610.36 
  
  
  
  
  
  
  
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