• Faq

Frequently Asked Questions


1、What is the beam size?

The beam size depends on the type of the laser diode and the lens systems. The beam sizes specified in our data sheets refers to the diameter of the collimated laser beam (FWHM) measured at the exit face of the housing.

2、What is beam divergence?

Beam divergence specifies how much a beam spreads out over distance. All our beam divergence specifications are full angle values.

3、What is boresight accuracy and pointing stability?

Boresight accuracy known as pointing accuracy, it is a measure of the angular difference between the beam propagating axis (where the laser beam is pointing) and the mechanical axis (where the laser housing is pointing). Pointing stability is a measure of how much the beam alignment drifts over a period of time.

4、How do I select a fan angle for laser lines?

The fan angle of a laser line specifies the angular spread of the laser beam at a particular distance. The length of the line (L) produced at a certain projection distance (D) is given by the formula L=2Dtan(q/2);where q is the fan angle. We have line lasers available with fan angles of 4, 15, 30, 45, 60, 75 and 90 degrees.

5、What determines the visibility of the laser light?

The visibility of a laser light depends on several factors. The first factor that determines visibility is the output power of the laser. The higher the output power, the higher the visibility. Wavelength also determines the visibility of the laser light. The human eye has a spectral response from 400 to 700nm with peak responsivity at about 550nm. So a 1mW, 635nm red laser is about 5 times brighter than a 1mW, 670nm red laser, and 3times brighter than a 650nm laser, even though they both have the same output power of 1mW. Lastly, ambient lighting also determines the degree of visibility. High ambient lighting levels at the target will yield low contrast and therefore low visibility. The best visibility generally occurs in presence of low levels of ambient lighting.

6、What is the effect of temperature on the wavelength of lasers?

The wavelength of a laser diode module shifts about 2 nm with every 10 degree rise in temperature.

7、What determines the lifetime of a laser module?

Typical lifetime of laser diode modules are 25,000 to 50,000 hours. If the laser diode temperature continues to rise exceeding the maximum operating temperature, the diode can be catastrophically damaged or the long term performance may degrade significantly. If the laser diode’s operating temperature is reduced by about 10 degrees, the lifetime will statistically double. Laser module lifetimes can be extended significantly by maintaining the case temperature at the low end of the operating temperature range. Heat sinks are recommended and must be used if the laser is operating constantly. Operating the laser modules at the low end of the recommended voltage range will also help to extend the lifetime of the laser.

8、How do you rate your output power?

The output power is the maximum power value at the exit of the laser housing. All our lasers have their power rated after passing through the optical assemblies. The power is measured according to CDRH specifications. Each laser is classified by measuring the amount of optical power that would enter a 7 mm aperture that is located at a distance of 20 cm from the laser source. Our line lasers have a lower classification rating because the laser power is spread along the length of the line.

9、Can we operate the TTL lasers in CW mode?

You can operate the TTL series lasers in CW mode. For CW operation, just connect the white wire to the red wire.