Laser color display device possessing three primary colors of red, green and blue

The invention relates to a red, green and blue three primary colors laser color display device, which comprises red laser, green laser and blue laser, wherein three coherent blanking device are corresponding positioned on the output optical path; first reflecting mirror, liquid crystal optical valve, beam cementing prism are positioned on the red output optical path after beam coherent blanking; second liquid crystal optical valve, beam cementing prism are positioned on the green output optical path after beam coherent blanking; a reflecting mirror is positioned on the optical path of blue laser; third liquid crystal valve id positioned between reflecting mirror and beam cementing prism; projection lens system is positioned on the optical path of output light after beam cementing prism.