A compact fully solid state instrument which produces an intense beam of light at a wavelength of 630nm and can be mounted directly upon a standard type optical bench. An adjustable collimator is incorporated providing focusing facilities and control over beam divergence. A useful feature is the modulation facility which permits experiments in laser communications and speed of light investigations to be carried out. Modulation may be demonstrated by means of the built-in oscillator, or from an external signal source. For these applications an accessory receiver unit is available. The case has rubber feet and a threaded bush for attachment of items from the mounting kit, B8A46152. A key operated ON/OFF switch is incorporated. (Please contact customer services if a spare key is required).• Power output: 0.9mW nominal, 1mW absolute maximum.• Category Class: 2 with Wavelength 630nm.• Beam divergence: 1 mrad approx. at optimum focus.• Modulation capability: Analogue or digital.• Internal modulation: pulsed at 1MHz, pulse width 0.1μs.• External modulation: 1V peak to peak max., 100Hz to 1MHz, input impedance 50Ω.• Modulation input connectors: 3.5mm jack sockets.• Operating voltage: 8 to 12V d.c. from internal PP3 type battery (alkaline recommended), and from smoother and regulated source via power in’ socket.• Current consumption: 50mA typical, giving approximately 9 hours operation from alkaline PP3.• Dimensions: 160 x 65 x 72mm overall (including collimator).• Mass: 400g.