Device converting non-polarized laser to linearly polarized laser

The invention provides a device converting non-polarized laser to linearly polarized laser. The device comprises a polarization beam splitting mirror, a first polarization maintaining mirror, a 1/2 wave plate, an electronically controlled phase retarder, an electronically controlled phase delay control host, a second polarization maintaining mirror and a polarization beam combining mirror. The polarizing beam splitting mirror divides incident non-polarized laser into linearly polarized light 1 and linearly polarized light 2, wherein the polarization directions of the linearly polarized light 1and the linearly polarized light 2 are perpendicular to each other. The linearly polarized light 1 passes through the first polarization maintaining mirror and the 1/2 wave plate. The vibration direction of the light vector is rotated by 90 degrees, and the light comes into the polarization beam combining mirror. The phase of the linearly polarized light 2 is changed by the electronically controlled phase retarder, and t