Laser TV, Laser projector and other lasersmonitorIt is an attractive product and should extend the scope of laser diodes (LD). Especially small lasersProjectorThe potential is great to become an innovative product. Recently, the small laser projectors integrated into mobile phones and projectors on car dashboards have attracted a lot of attention. Many other interesting applications have also been offered. Assemble these small laser projectors, the very compact lasers are the light sources necessary to make the three primary colors of red, green and blue.
For red and blue, the use of laser diodes is a very simple and compact approach. For green, the second harmonic output by infrared lasers is generally used. Lasers in a solid diode chip or stabilized lasers of wavelength are alternatives to infrared transmitters. These compact lasers have much brighter brightness than conventional light sources, light sources block or diodes emitting light. This high brightness minimizes the size of the projector’s optical elements without having to spend a lot of light stream of the projector and brightness of the projected image. In addition, the effectiveness of laser wall insertion (WPE) is much higher than that of conventional light sources. Battery life is one of the most important indicators of mobile products. A high brightness and a high WPE are not only the advantages of lasers, but also important requirements for lasers.
In the range of visible red light wavelengths, people want the wavelength short and the higher the brightness, because as the wavelength of the light source is shorter, the higher the sensitivity of the human eye. A 660 Nm laser diode is a good DVD development and marketed DVD disc application. However, forto showFor applications, shorter wavelengths (~ 640 nm) are necessary because the sensitivity in the eyes of 640 Nm is almost three times that of 660 Nm. The output power of 640 Nm LD must be greater than 50 MW. But it depends on how the projector is implemented.
For ~ 640 Nm laser wavelengths, an Algainp material system is generally used. Since the conduction strip of the conduction strip between the active layer and the coating is low, the main factor limiting the LD WPE Algainp is the thermal saturation caused by the carrier of the active layer. In addition, the smaller gap is due to shorter wavelengths, as there are higher quasi-fermi levels in the active layer. Consequently, the abolition of the leak is an urgent need to reach short wave Algain with a high WPE. The main limitation of the maximum output of narrow stripes ALGAINP LD is the catastrophic (cod) optical damage to the facet mirror. In order to reach high light and high density optical power on the surface of light, passivation of the light surface is an important way to overcome the degradation of the COD.
Several known methods are used to implement a small laser display. One of them is called a mirror scanning method. This method uses a MIM mirror to scan the collimated laser beam. The laser beam spot on the screen is quickly moved to scan and reflect it. During the scanning process, the laser power of each color is adjusted to represent the correct color of a pixel by a. This method requires a small beam on the screen. Therefore, the unilateral mode and the laser output limited by diffraction are preferred. In this work, we use a red LD with a narrow crest scratch structure to control the lateral pattern.
The schematic diagram of the narrow LD crest is illustrated in Figure 1. The epitaxial layer is cultivated on dislocation GAAS of type N to prevent the spontaneous order of Algainp. The luminous guide wave is strongly constrained using an Alinp coating with low refraction index. The largest coefficient of light stress of the active layer reduces the density of the support holder. The width of the LD chip is 200 μm and the length of the cavity is 1500 μm. The chip is assembled in a 5.6φto package, with a downstream configuration, with welding ausn and installed. The ZN is used for the non -absorbent window process, using ZN as a source of ion doping, and by high temperature receipt, the energy deviation of the final surface is improved. Once the electrode is finished, the AR and HR films are dissociated and tackled.
