For the eyes,Laser safety glasses are important. If there is no Laser safety glasses, thenthe use of laser cutting machine staff will be blind. So people who operate thelaser cutting machine to use Laser safety glasses. This article will introduceour initial attempt on this idea, and the development of this feature with thisnew laser protection glasses characteristics and role, given a detaileddescription.
First,the new laser protection glasses structure lens for the focal length of thevariable lens, photosensitive chip is used CMOS chip. Although CMOS in thesensitivity, resolution and signal to noise ratio, such as CCD, but here forordinary visual applications have been enough, and CMOS itself has a certainadvantage. First, it is directly output digital signal, and mathematical chipconvergence for a high degree of integration; Second, because the imageacquisition in different ways, CMOS power consumption is only 1/3 of the CCD;CMOS cost is much lower than the CCD cost. Optical signal processing part (ie,the main part of the motherboard) is used mainly DSP and FPGA chip, used tocontrol the CMOS acquisition image, and its output signal processing afterimaging in the micro-display.
Thissection also connects a control handle (for providing battery power andexternal reception control instructions). The FPGA receives commands from thecontrol handle to control the CMOS parameters such as exposure time. Thecontrol DSP performs image brightness such as brightness, contrast, That is,red, green, blue three channels of strength) and other aspects of thetreatment, in addition, you can also control the lens for automatic focusadjustment. Micro-display is used in OLED ultra-micro display, due to volumeand accuracy constraints, ultra-micro OLED current resolution is still not highenough, this is the development of this component a technical bottleneck, butwith the continuous progress of technology, Higher resolution clearer AMD willcontinue to produce.
Atpresent its resolution is mainly 640 480. The purpose of the eyepiece is toenlarge the image on the tiny display so that the objects shown above and theobjects in reality are imaged in the human eye as close as possible to thevisual experience. Its focal length can be adjusted appropriately to fit theeyes of different eyesight, so that even myopia can wear this goggles directlywithout wearing myopia.
Second,the role of new protective goggles in laser protection Eye and eyes outside thelight completely separated, if the protective mirror is not connected to thepower, the front will be a dark, just like to bring a thick goggles like.Therefore, in the case of wearing this glasses, even if the laser suddenly scatteredto the direction of the eye, which at most make the CMOS output signalbrightness increases or even saturation, the eyes feel only the displaybrightened; if the laser beam, such as direct To the eyes of such an accident,if the laser intensity is weak, the result may be made CMOS sensor saturationor even severe saturation, the eyes will see a white display, if the laserintensity is high, the result may be broken CMOS sensor or burned protectiveglasses On the plastic frame, but will not cause any harm to the eyes.Therefore, this protective glasses on the human eye laser protection is safe,does not occur laser damage to the eyes of the situation.
Itcan be seen that the scattered light is quite strong, but the wavelength of thelaser is 900nm, with the naked eye we do not see anything on the metal surface,but the laser does exist, and the naked eye does not perceive its presence andposition , So the damage to the eye is inevitable. This is also dangerous forthose who are also working around the laser rather than using a laser beam.
Ifthere is no glasses, because too dazzling, we can not use the eyes directlyobserve the spot; if forced to see the eye for a while, then look at otherobjects, it will be vague vision, need to adapt to a job. But if converted intoa protective mirror display images, we will only observe the light green show,the eyes will not feel uncomfortable. Because the human eye is more sensitiveto green light, so even if there is a little green laser, the human eye willreact strongly. Laser power is only 200mW, relative to Figure 2 2W non-visiblelight power is much weaker, we can see if you do not wear laser protectionglasses, which will have more laser radiation into the eyes, the damage to theeye much larger, but we Can not see it.
Apair of femtosecond lasers with a diameter of 2mm, a power of 25mW and awavelength of 750nm are hit on the hands or skin. We basically do not feel it,but if we shoot into the eyes, we will burn the vitreous and retina. Figure 5shows the image of the laser beam when the laser beam is partially directed tothe CMOS sensor chip of the goggles. It can be seen, CMOS chip has beenseriously saturated, then the feeling of the eyes will be the front of themonitor suddenly brightened white, but the eyes themselves without any damage.Because the power is weak, although the CMOS has been saturated, but did notburn its photosensitive surface, so the protective mirror can continue to use.Through the experiment we learned that our new type of protective glasses inthe protection of the eye is not selected laser wavelength, regardless of red,green, blue or even ultraviolet laser or infrared laser, it can play 100%protection Role, this performance is the traditional protective glasses can notmatch.
Third,the new laser protection glasses in the laser operation and the use of othereffects in the process of its strength reduced to 50% of the original, when theintensity reduced to the original 20%, the image of the green component is basicallygone, we can Through the handle of the image brightness of the appropriateincrease, so that the light can be gently adjust the control laser. What kindof image is appropriate, which is different, the user can adjust the imageparameters according to their own requirements.
Peoplein the adjustment of lasers, especially the oscillator, the laser before thestart, often with fluorescence to align the laser light path and adjust thevarious frames, but the fluorescence is generally weak, and if the nearinfrared light, naked eye can not see, People often use infrared night visionto observe the fluorescence position. But because of its larger, it is not veryconvenient to use, if we use our new protective glasses, whether to see thisfluorescence? The answer is yes. In the spot is the titanium sapphire laseroscillator fluorescence in the mirror on the image, you can see, the spotrelative to the background light is still more obvious, if closed or weakenedindoor light intensity, the effect will be more significant, see 8 (b ).Because of our new type of protective glasses with CMOS photoelectric imagedetection and DSP high-speed digital image processing functions, so that it hasdescribed several features above, so as to laser adjustment and laserapplications has brought great convenience.
Fourth,the conclusion of this article describes the laser protection glasses with thetraditional laser protection mirror is almost completely different from thedesign concept, therefore, to achieve the true separation of the human eye andthe laser, the eyes played a very safe protective effect, its unique figuresFunction for people to adjust the laser provides a great convenience.
Theuse of this new type of Laser safetyglasses will makethe first-line laser operation no longer a dangerous work, and it is a verynecessary means of protection in laser laboratories. In the life of peoplelaser protection mirror to maintain their own eyes. Laser safety glasses One ofthe tools to be prepared for people who use laser cutting machines. And is thenecessary tool in the work is the Laser safety glasses.