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Image Samples - Interactive Programming Machine |
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| Above left: Freehand drawing made by copying an illustration from a book. |
Above right: Drawing made by "tracing" the laser image over artwork (a child's placemat). |
| The frame rate for both images was 20 Hz, and the data rate was 2560
points per second. In modern ILDA parlance, that's only 2.5K tuning! The output of the
programming machine was actually rolled off with a low-pass filter, to smooth out the
drawing points. Of course, this is the antithesis of present day laser image projection,
with its emphasis on small signal bandwidth. Standard G-100PD scanners were used, with A-600 drivers. The images could be displayed at full 40 degree deflection, with no distortion. The 20 Hz refresh rate gave rock-steady images completely free of flicker. Although closed-loop scanners were used for these images, the machine was capable of displaying similar images with open-loop G-1 scanners. Beam blanking was accomplished with a metal vane rotated into the beam by a scanner. Question: are modern laser images, made with 50,000 points per second, really 20 times more complex than these old images? I also have to wonder why so few of the laser pictures on the Internet specify the frame rate. Could it be that some of the frame rates are so slow, the images are flickering? Next: try the drawing process yourself, with a Java Applet |
