Photonic Products in Hatfield Broad Oak, England, added TTL modulation options to its Photon range of laser-diode modules, which will accept signals from DC up to 100 kHz minimum. The laser modules are for applications in which detection of the laser beam in high-ambient-light conditions is vital, such as security systems and safety barriers. Modulation options are available on all Photon laser modules, with wavelengths from 635 to 830 nanometers, and output powers from 0.9 to 32 milliwatts. Customer-adjustable lens for collimated or focused beam can be replaced by other optical systems such as line generators. Operating voltage is from 2.7- to 6-volts DC for continuous-wave modules and 4- to 12-volt DC for modules with TTL modulation. The modules, either cylindrical or with a 25-millimeter mounting flange, consist of an anodized aluminum housing, laser diode, drive circuit, and collimating lens. Mechanical dimensions are 12 millimeters in diameter by 43 millimeters in length. They can be supplied in various colors to assist in wavelength or power identification. For more information, contact Photonic Products on line at www.photonic-products.com.