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Laser diode light sources have been used for decades in the consumer and industrial fields for optical mice, CD and DVD players, office scanners, laser pointers, virtual keyboards, barcode scanners and surgery. There is currently a general increase of applications using laser diodes, largely for their inherent benefits in terms of high brightness and light coherence.
Product safety class:
- All the products that include laser diodes or high power lamps are subject to regulations and are sorted in classes. In general the classes are defined according to the amount of light per area, and define the level of hazard to the human eye.
Therefore any devices available on the market, such as high power video beamers or halogen lamps can potentially be dangerous for the human eye if observed direcly from a short distance.
- There are however various ways to reduce the class safety for a laser-based device. As an example, for a standard laser pointer for which the laser beam is static, the resulting class will be higher than for the same laser pointer with a scanned beam. Such an effect is used in the Lemoptix MEMS micro-projector to considerably reduce the level of hazard to the human eye.
- Furthermore, the Lemoptix projector does not use laser focusing techniques to project images, which will then concentrate all the laser power in a very small spot. but rather uses collimated laser spots (parallel laser beam),
There are 6 different safety classes, from the lower to higher intensity (cf. official classification document IEC 60825-1 standard)
- 1 - A class 1 laser is safe under all conditions of normal use
- 1M - A Class 1M laser is safe for all conditions of use except when passed through magnifying optics such as microscopes and telescopes
- 2 - A Class 2 laser is normally safe in the visible range because of the eye blink reflex limits the exposure time
- 2M - Same as class 2M if not viewed through optical instruments
- 3R - A Class 3R laser is considered normally safe if handled carefully, with restricted beam viewing. Direct beam viewing may be hazardous.
- 3B - A Class 3B laser is hazardous if the eye is exposed directly
Warning labels
- In the consumer and industrial markets, warning labels and safety classes are today widely used in many devices, to warn the user of possible risk associated to lasers. Warnings such as : " do not stare at the projector light source ", "do not stare under direct exposure" are largely common and accepted by the users.
Lemoptix specific added safety apparatus
- To further minimize the risk for any users of laser-based micro-projectors, Lemoptix has added a unique technical feature to prevent beaming the light in case of an unexpected default of the projection system or if the laser light power exceeds the initially defined threshold.
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