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EDL2 Laser Diode Driver IC/Circuit released
Economic and powerful for the APC laser diode driver and negative close-loop feed back driver application.
10~350mA, TTL modulation with APC laser diode driver control and over current protect setting for JQA/TUV safety certification .

F5.6mm Blue Laser Diode released
Dia. F5.6mm 405nm/445nm blue laser diodes are successfully developped in mass production. EGISMOS is willing to support the special price close to the market expection. They come in various power selection ranging from 20mW, 50mW and 500mW.

Mini DPSS Green Laser Modules released
Dia. F8mm DPSS green laser modules are successfully developped for the application where size and visible brightness matters the most. They come in various power selection ranging from 1mW to 100mW. The smallest dimension F8mm x 30mm.

Mini S4 Series Red Laser Modules released
Dia. F4mm x 10mm red laser modules are successfully developped for the application where size matters the most like mobilephone, portable application. They come in various power selection ranging from 1mW and 5mW.

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You Only Received One Set of Eyeballs?

Lasers have tended to be highly glamor devices popular with hobbyists, experimenters, entertainers, and serious researchers alike. However, except for very low power lasers - those with less than a fraction of a mW of beam power - they do pose some unique hazards particularly with respect to instant and permanent damage to vision.
Here we only discuss the hazards with respect to vision. There are other safety issues - such as the danger from the high voltages used to power certain types of laser. These are summarized later in this chapter and dealt with in more detail in the chapters on the lasers for which they apply. There are several reasons that even small lasers which do not represent any sort of burning or fire risk can instantly and permanently damage vision:

The output of many lasers is a nearly parallel - highly collimated - beam which means that not only is the energy concentrated in a small area but the lens of the eye will focus it to a microscopic point on the retina instantly vaporizing tissue in much less than the blink of an eye. A collimated beam represents the rays from an object at infinity so if your eye is focused for distance, the laser will be in focus as well. Even a common helium-neon laser without external optics will approximate a point source a .5 meter or more behind the exit window of the laser. If you are working in a small room, this approximate distance would likely be where your eyes are focused. While purists might argue that the lens of the eye isn't perfect and will not produce a diffraction limited spot on the retina, this won't save your vision! The power density in a sub-optimal spot can still be astronomical.
A cheap laser pointer also produces a highly collimated beam.

Even at power levels considered relatively safe, one shouldn't deliberately stare into the beam for any reason. For these relatively low power lasers, permanent eye damage is not that likely but why take chances? For these lasers, viewing the spot projected on a white surface is perfectly safe.

A 100 W light bulb puts out about 5 to 7 W of visible light and another 35 to 40 W in the near-IR which is also relevant since it passes through glass, water, and the anterior structures of the eye can be focused on the retina. The rest is mid to far-IR and heat with a small amount of UV tossed in. All of this radiation is more or less uniformly distributed in every direction. However, at any reasonable distance from the light bulb, the power density (e.g., W/mm2) entering the eye is much lower than for a collimated laser beam of even very low power. And, it takes significant effort to produce any sort of truly collimated beam from such a non-point source such as is present with even the filament of a clear light bulb. For a frosted light bulb, insert another factor of a thousand or so. :) Without collimation, even the portion of that additional 35 to 40 W of near-IR that enters the eye isn't going to cause damage. However, for a helium-neon laser, the collimation is such that the entire beam (total power output of the laser) will still be small enough to enter the eye even at a distance of several meters.

For example, at 10 cm from a 100 W bulb (which would be a very uncomfortable place to be just due to the heat), the power density of the visible light (assuming 5 total watts) would be only about 0.05 mW/mm2. At 1 m, it would be only 0.0005 mW/mm2 or 500 mW/m2. Based on this back-of-the-envelope calculation, a 5 mW laser beam spread out to a circular spot of 0.1 m diameter (i.e., 1 mR divergence at a distance of 50 m - without external optics) will appear brighter than the 100 W light bulb at 1 m! And, close to the laser itself, that beam may be only 1 *mm* in diameter and thus 10,000 times more intense! (And note that the other invisible radiation that passes through to the back of the eye is still not nearly as dangerous as the beam from the 1 mW laser because it isn't focused to a tiny spot by the lens.)

As another point of reference, the mid-day Sun at the Earth's equator on a clear day has a power density of about 1 kW/m2 or about 1 mW/mm2. It would not take very long staring into the Sun to burn out your eyeballs!

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Typical Laser Diodes

The most common laser diodes of visible wavelength have 635nm, 650nm for red laser, and 405nm, 445nm for blue laser. As the green laser diode, it's still in developing period. Most green laser still use the DPSS(Diode Pumped Solid State) way to create the 532nm laser by 808nm laser diode......more

Laser Module, laser pointer Specifications No.1

Wavelength: Usually, closer to 540nm is better since visibility is a strong function of wavelength. However, the variability can be significant - a laser pointer at 640 nm could indeed be closer to 650 nm and there's almost a 2:1 ratio of relative brightness. Or 450 nm blue laser could be much brighter than 405 nm......more

Diode Laser Safety

As the CE of Europe safety rule requests class 1 <0.39mW, class 2 <1mW of collimated laser for the consumer products would emit the laser to the eyes. And the FDA of USA allow the class 3A <5mW for the consumer products. As the detail safety rules would be different for different applications and area, you also can contact EGISMOS to inquire......more

Laser Module, laser pointer Specifications No.2

Distance/range: Laser light doesn't travel a specific distance and stop, or suddenly become too dim to be seen. It's only possible value would be in comparing various models, they probably just associate a particular value with the output power, wavelength, or the the laser spot size of the operating distance......more

 
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