From The Laser Guidebook


The helium-neon laser probably is the most familiar of all lasers. The least-expensive gas laser, it has long been the standard choice to demonstrate laser physics in schools, colleges, and museums. In its most familiar form, the He Ne emits a fraction of a milliwatt to tens of milliwatts (mW) of red light at 632.8 nanometers (nm). As such, it has long been the most common and most economical visible laser.

The helium-neon laser was among the first lasers demonstrated, and was the first gas laser (Javan et al., 1961). Initial versions emitted at 1153 nm in the infrared, but other researchers soon found that the same gas mixture could lase in the red (White and Rigden, 1962). Other lines were produced in the laboratory, but the strong 632.8-nm red line has long been the most important because it made up to about 50 mW available at a visible wavelength. Sales have climbed over the years, and were nearing the half-million mark in 1990 ( Lasers & Optronics, 1990).

However, important changes are in the offing. Red semiconductor lasers were developed in the late 1980s. Although they cost more than near-infrared semiconductor lasers, the prices of red semiconductor lasers are dropping, and they have become competitive with red heliumneon lasers. Semiconductor lasers have important advantages, including smaller size, higher efficiency, and no need for the high drive voltage used in gas lasers. They cannot replace all red helium-neon lasers because the gas lasers have better coherence and beam quality,...

Products & Services
Audio Cables
Audio cables transmit audible signals such as voice and music. They are designed to minimize noise and interference that can impair sound quality.  Audio cables connect an audio source such as a stereo or microphone to an audio receiver or output such as speakers. Most products are shielded to prevent electromagnetic interference (EMI), typically with a foil and/or braided shield.  
VGA Cables
VGA cables use three-row, 15-pin video graphics array (VGA) adapters to connect video and computer monitors, video cards, and some high definition televisions (HDTV). They carry analog signals rather than digital signals, including RGBHV and VESA DDC data.
Coaxial Cables and Triaxial Cables
Coaxial cables have an inner conductor insulated by a dielectric material and then surrounded by an outer conductor that is shielded with braid or foil. Triaxial cables add an extra layer of insulation and a second conductive sheath. They are commonly known as coax and triax, and are chosen because of their protection against external electromagnetic interference.
Cable and Electrical Tapes

Cable and electrical tapes are a variety of pressure-adhering adhesive tape specifically designed to wrap, shield, mask, mark, or insulate types of electrical cables, wiring harnesses, electric components, or circuit boards. Electric tapes come in many colors and materials, but black, vinyl tape has become the consumer standard.

HDMI Cables
High-definition multimedia interface (HDMI) cables are assemblies of audio and video cables that are used to transmit digital audio/video signals. They are used to connect digital devices such as set-top boxes, personal computers, and camcorders to compatible computer monitors, video projectors, and digital televisions. HDMI uses a single cable for the transmission of uncompressed digital data and implements the EIA/CEA-861 standards.  

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