@ -71,7 +71,7 @@ Fig. 1. Direct vision : the pencils of each visible point souces intercept the p
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Fig. 2a. Image vision : an optical imager (rectangle) has modified the incident pencils. Only pencils from image points enter my eyes. here the image points are real.
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Fig. 2b. here the image points are virtual.
#### Optical imager and basis physical principles.