ambient light - 06/10/99 EDN Design
Idea In some applications, you need to detect light signals in the presence of background light whose
intensity can change by orders of magnitude. The circuit in Figure 1 uses an integrated photodiode/amplifier
(OPT201) in. . . [by Massimo Gottardi, IRST, Trento, Italy]
Clear Fluid Detector #2 - Using an ultra low power technique, this circuit detects when a clear
fluid is inside a piece of clear plastic tubing. It can be used for fluid level control and monitoring . . .
[Circuit by Dave Johnson P.E., 10/22/05]
Color Film Makes Optical Filter - This isnít an electronic circuit but the file shows the curve for an
optical filter made from exposed color film. The material blocks most visible light but is very transparent
to 880nM infrared light. Kodak 100ASA is exposed to "cool white" fluorescent light for about 5 seconds . . .
[Circuit by David A. Johnson P.E., 01/01/98]
Color Sensor - Colour sensor is an interesting project for hobbyists. The circuit can
sense eight colours, i. e. blue, green and red (primary colours) ; magenta, yellow and cyan (secondary
colours) ; and black and white. The circuit is based on the fundamentals of optics and digital electronics.
The object whose colour is required to be detected . . .
Color Sensor - This is a circuit for a color sensor which uses three LDRs to detect the
color of object placed in front of it and indicates the same by glowing a corresponding color LED among 8
LEDs. . . . [© EFY Enterprises Pvt. Ltd. All rights reserved]
Color sensor circuit - I built this color
sensor to equip my third implementaton of brick sorter. Michael Gasperi presents such a sensor in an article
of Nuts and Volts magazine. His circuit is based on an input multiplexor. Three CdS photo-resistors,
connected to this multiplexor, receive light through RGB colored filters (cleverly done with Lego transparent
bricks). . . . [Philippe "Philo"Hurbain]
Color Sensor for Robot - I'm developing a simple, active, color, object sensor for my robots
based on three ultra-bright LEDs. An old-fashioned cadmium-sulfide sensor detects the brightness of the
reflected red, green, and blue as each is turned on individually. . . .
Solar Powered Light to Flasher
- The circuit converts an off-the-shelf solar powered LED path light from producing a steady state light to
one that produces a flash. This circuit includes a tiny dual Schmitt trigger inverter IC which form the pulse
generator and the daylight sensor circuit. The circuit produces a positive pulse, which feeds the constant
current LED driver circuit. . . . [Circuit by David A. Johnson P.E., 03/02/10]