25 b and the transparent insulating layer 24 then an exposure light source 26 is provided in a direction from the second surface 21 d toward the first surface 21 c of the transparent substrate 21 by using the first gate pattern 23 a and the second gate pattern 23 b as a light shielding layer such that the photoresist layer forms a first photoresist pattern 27 a on the first region 251 a of the first polysilicon pattern 25 a and a second photoresist pattern 27 b on the third region 251 c of the second polysilicon pattern 25 b in other words the array substrate 20 of the embodiment of the present invention uses the first gate pattern 23 a and the second gate pattern 23 b which are located below as a light shielding layer such that the first photoresist pattern 27 a and the second photoresist pattern 27 b can be formed without the need of a mask process in one embodiment in a direction of top view or bottom view of the transparent substrate 21 the first region 251 a and the first gate pattern 23 a therefore have an identical first patterned shape and the third region 251 c and the second gate pattern 23 b also have an identical second patterned shape please further refer to fig2 c a first doping step 255 is performed to.