The Dpl Low Noise Intracavity Frequency-doubling Laser And Its Applications

At the end of 20 century,digital technology developed rapidly,and digital products take place of traditional products and instruments,such as digital camera etc.. New business brings new requires. Digital color developing and enlarging system is brought forward in that background. Laser beam is the perfect light source with high saturation,high precision and high power,to explore the printing paper. Especially in the field of the green and blue DPSSL(Diode pumped state-solid laser),intracavity doubled-frequency DPSSL has the advantages of long lifetime,compactness and high efficiency etc.. So it has had a wide variety of applications in the field of light storage,laser printer,optical information transmission,laser rangefinder and laser medical etc..We do many researches of intracavity doubled-frequency DPSSL and the application of laser digital color developing and enlarging system,and obtain some useful results. The paper is supported by the Significant Project of National Education Committee.At first,we introduced the velocity equation of DPSSL,which operates in the multi- longitudinal modes. Then,we give the dynamic equation of intracavity doubled-frequency DPSSL,when we take in the SHG(Second harmonious wave generation) equation. On the base of that,we simulate the light power of the intracavity doubled-frequency DPSSL. We point out the reason of "green problem",and analyze the influence of the main factors. It offers the theory of new precept to decrease the infection of "green problem" .Realizing the excellency of Nd:YV04 crystal,we use Nd:YV04/KTP firstly in our experimentation. The loss of light with different polarized orientation is different,when it through Nd:YV04 crystal. Utilizing the case and changing the thickness of KTP crystal bycontrolling temperature,we get a narrow light filter,so the cavity operates with single longitudinal mode. When the pumped light was 300mW,we gain the green light about 5mW. The noise is lower than 2% in 10 hours.An other time,we use Nd:YV04 crystal and compensator firstly. The loss of light with different polarized orientation is different,when it through Nd:YVO.i crystal. So it can select different linear polarized light. The compensator compensates the change of polarized light,and also controls the polarized orientation. In result,we get a cavity,with the orientations of the linear polarized multi- longitudinal modes are agree. The noise of green output reducing,the cavity is steady with multi-longitudinal modes operating. The laser give out 10.7mW green light,pumped 900mW. We observed it for 40 hours,the noise of green power is lower than 1%. We optimized the laser cavity later. The length of cavity is shortened by 5mm and the result of experiment is pleased. When the pumped light was 400mW,we gain the green light about 8mW.