Other Parts Discussed in Thread: DLPLCRC900DEVM
Hi,
I am using a red laser to illuminate the DMD with the goal of imaging the DMD surface. As shown in the figure below, there are two 4-f systems before camera.
L1 and OL1 forms the first 4f system; OL2 and L2 forms the second 4f system. L1, L2 are identical; OL1, OL2 are also identical.
So this system is imaging DMD surface on the camera without maginification or demagnification.
However, the image we get has some obvious diffraction at the edge of a random pattern we load on DMD. This pattern also exist when we switch to a broadband light source. The figures below are under laser and broadband source, respectively. The size of the smallest square here corresponds to 40x40 pixels on the DMD. Do you have any idea where does this come from? In presence of this diffraction, it seems that we can not make use of every pixel on DMD for modulation.