• 20MHz VCSEL 3mW LASER TEST CIRCUIT
  This circuit takes advantage of some new vertical cavity surface emitting lasers (VCSEL) that don’t require light output control circuits. The circuit shows how to drive the device from a single high speed CMOS IC. The circuit can easily be modified to transmit signals from kilohertz to about 50MHz.

• 40KHZ LED TEST SIGNAL GENERATOR
  This 40KHz crystal controlled oscillator circuit drives an infrared LED with powerful 40ma pulses.  The circuit can be used to test optical communications circuits, designed to receive 40KHz modulated light signals.

• 40KHz TV-VCR LIGHT SOURCE REPEATER
  This circuit is designed to be placed directly in front of a standard TV or VCR remote. The exiting light pulses produced by the circuit match the pulses from the remote but are about 10 times more powerful. Using the device, the remote can operate a TV or VCR over three times the normal distance.

• COLOR FILM MAKES OPTICAL FILTER
  This isn’t 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. Then, the film is developed in the usual way. The color negatives form the filter material and does a fine job of blocking visible light wavelength and passing the longer near infrared wavelengths.

555 Timer 40kHz Infrared Oscillator:  (electronic circuit added 9/03)

A Serial Infrared Remote Controller:  (circuit / schematic design added 6/06)

Active IR Motion Detector:  (circuit / schematic design added 6/06)

An Ambient-Light-Ignoring Infrared Active Motion Detector:  (circuit / schematic design added 6/06)

AN243: Fundamentals of the Infrared Physical Layer:  Microchip Application Note Published 19-Jan-04   (app note added 2/06)

AN657: Decoding an Infrared Remote using a PIC16C5X Microcontroller:  Microchip Application Note Published 26-Aug-97   (app note added 2/06)

AN756: Using the MCP2120 for Infrared Communications:  Microchip Application Note Published 4-Jun-01   (app note added 2/06)

AN888: Programming the Palm OS™ for Embedded IR Applications:  Microchip Application Note Published 8-Jan-04   (app note added 6/06)

AN941: Programming Windows XP® for Embedded IR Applications:  Microchip Application Note Published 27-Jul-04   (app note added 6/06)

AVR Based Serial Port IR Receiver:  (circuit / schematic design added 6/06)

Basic Infrared Light Train Detection:  (circuit / schematic design added 6/06)

Build an Infrared night scope:  (diagram added 2/07)

Cheap 40kHz Clock:  (electronic schematic / circuit added 4/02)

Computerized Infrared Remote:  control your stereo, TV and VCR from Windows, includes schematic and software (added 4/02)

Day and Night Infrared Detection:  (electronic circuit added 7/03)

Decoding an Infrared Remote using a PIC16C5X Microcontroller:  Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Decoding IR Remote Controls:  (circuit diagram added 1/07)

Digibox Interface:  (electronic circuit added 7/03)

Fire Stick Infrared Remote Control:  (electronic circuit added 7/03)

Fire-Stick infrared remote control:  (diagram added 2/07)

Fundamentals of the Infrared Physical Layer:  Microchip Application Note Published 19-Jan-04   (app note added 2/06)