The Lascells semiconductor laser contains two independently controlled laser diodes, one at the standard 650nm red and a second at 532nm green. Both lasers may be simultaneously passed through a double slit slide and both diffraction patterns may be displayed one above the other for an immediate comparison.
The unit is equipped with internal 1 MHz modulation which when used in conjunction with the laser receiver and an oscilloscope allows the speed of light to be determined in the laboratory. In addition, the facility to modulate the laser from an external source is provided allowing audio to be sent to the receiver from a smartphone or MP3 player.
The apparatus is switched on/off using a removable key, to prevent unauthorised use, and is supplied with a 9V power supply and full instructions.Also available is a dual purpose laser receiver, designed for use with the Lascells Dual Colour laser, the unit contains a planar chip photodiode tied to a 1Mhz amplifier for speed of light calculations along with an audio amplifier for demonstrating data transmission using light. The unit is powered by a 9V DC supply (included) and has a built in speaker for audio reception. The amplified audio is also brought out to 4mm sockets on the front panel for observation or connection to a secondary driver such as the Rubens tube.
When using the receiver for speed of light calculations the audio amplifier is disabled, with the signal brought to the front panel only for monitoring using an oscilloscope.