charlie@oakhill.UUCP (Charlie Thompson) (08/10/90)
The simpliest way to see near IR is with an old black-and-white security camera...like the type in 7-11 stores. They use (typically) a 7735 vidicon tube. The 7735 is sensitive to the IR emitted from IR LED's. It is a neat way to 'see' your IR LEDs. It's really handy.... hold an illuminated IR LED in your hand and focus the TV camera on it. You will see your hand with a little glowing spot where the LED is ..even though there is no visible light. A visible light filter could be placed over the 7735 to make sensitive to IR only. -Charlie Thompson