• Beam expansion: 10:1
• Effective range: 328 feet (100 m)
• Transmission efficiency: 95%

A laser collimator is used to limit the degree of spread (divergence) of a laser beam. Typically, a visible wavelength Helium Neon laser beam will diverge at a rate of 0.6 to 1.2 milliradians, depending upon the length of the laser cavity, and certain other optical characteristics. This means that a 1.0 mm beam exiting a laser will be approximately 1.0 m in diameter at 1000 m distance from the laser (assuming a 1.0 milliradian divergence). Correspondingly, the beam diameter at 100 m would be 0.1 m, or approximately 3.9 inches.

By inserting the ALC-10A collimator into the beam path at the laser exit, the beam spread can be reduced to approximately 0.44 inches (11 mm) at a distance of 328 feet (100 m).

The ALC-10A is constructed of chemically inert heavy wall PVC type I for physical ruggedness, and for resistance to handling abuse. It is sealed to prevent contamination due to moisture or airborne particulates. The lenses are broadband and AR (anti-reflective) coated to reduce beam transmission losses throughout the visible spectrum. Large input optics are used in the ALC-10A to accommodate some misalignment of the beam exiting the laser (lack of concentricity with the mechanical housing). Except in extreme cases, this feature eliminates the need to realign the laser tube to improve its concentricity with respect to the centerline of the collimator mounting bezel.

Focusing, or collimating, the laser exit beam is accomplished by rotating the exit end of the collimator. In so doing, the distance between the input and output optics of the collimator are altered, thereby effecting the focal plane of the lens combination. the beam diameter can therefore be adjusted throughout the effective range of the collimator.

The ALC-10A is furnished with a standard 1-32TPI male threaded interface so as to mount directly to all Jodon lasers. It will mount directly to all other manufacturers’ lasers that incorporate a 1-32 internally threaded nose bezel.

SPECIFICATIONS

Optimum wavelength	632 nm
Exit aperture	1.250 inch (32 mm)
Input beam diameter	1.5 mm maximum
Divergence reduction	8-10:1
Spot size at effective range (assuming a 0.8 mm round cross section entry beam @ TEM00)	0.44 inch dia (11mm)
Depth of field (distance at which beam will not exceed 1.4 times the spot size)	1000 ft (300 m)
Dimensions	8.80 L x 1.9 dia inches (220 x 48.3 mm)
Weight	14 ounces (395 g)
Material	Gray PVC Type I
Jodon part number	139