Optical depolarizer

1. An optical depolarizer, comprising:

a light-combining module comprising a birefringent prism, wherein an optic axis of a first crystal of the birefringent prism forms a 90° angle with an optic axis of a second crystal of the birefringent prism; and

a depolarization module, wherein the depolarization module is disposed at a light emitting end of the light-combining module, the depolarization module comprising:

i) a light-splitting component, wherein the light-splitting component separates orthogonally polarized light into a first light beam and a second light beam, wherein a polarizing axis projection of the light-splitting component on an emitting plane of the light-combining module forms a 45° angle with the optic axis of the second crystal of the light-combining module,

ii) a delayer, wherein the delayer is configured to delay a propagation of the first light beam,

iii) a light-combining component, wherein the light-combining component combines the second light beam and the first light beam.

2. The optical depolarizer of claim 1 , wherein the light-splitting component is a polarization beam splitter and the light-combining component is a polarization beam combiner.

3. The optical depolarizer of claim 1 , wherein the delayer is a glass piece or a third birefringent crystal.

4. An optical depolarizer, comprising:

an isolation module, the isolation module comprising a first wedge, a rotator disposed at the light emitting end of the first wedge, and a second wedge disposed at the light emitting end of the rotator, wherein a crystal axis of the first wedge forms a 45° angle with a crystal axis of the second wedge; and

a depolarization module,

wherein the depolarization module is disposed at the light emitting end of the isolation module, the depolarization module comprising:

i) a light-splitting component, wherein the light-splitting component separates orthogonally polarized light into a first light beam and a second light beam, wherein a polarizing axis projection of the light-splitting component on an emitting plane of the second wedge forms a 45° angle with the crystal axis of the second wedge,

ii) a delayer, wherein the delayer is configured to delay a propagation of the first light beam,

iii) a light-combining component, wherein the light-combining component combines the second light beam and the first light beam.

5. The optical depolarizer of claim 4 , wherein, the light-splitting component is a polarization beam splitter and the light-combining component is a polarization beam combiner.

6. The optical depolarizer of claim 4 , wherein the delayer is a glass piece or a birefringent crystal.

7. An optical depolarizer, comprising:

a light-combining isolation module, the light-combining isolation module comprising a first polarizer, a rotator disposed at the light emitting end of the first polarizer, and a second polarizer disposed at the light emitting end of the rotator; and

a depolarization module, wherein the depolarization module is disposed at a light emitting end of the light-combining isolation module, the depolarization module comprising

i) a light-splitting component, wherein the light-splitting component separates orthogonally polarized light into a first light beam and a second light beam, wherein a polarizing axis projection of the light-splitting component on an emitting plane of the second polarizer forms a 45° angle with the optic axis of the second polarizer,

ii) a delayer, wherein the delayer is configured to delay a propagation of the first light beam,

iii) a light-combining component, wherein the light-combining component combines the second light beam and the first light beam.

8. The optical depolarizer of claim 7 , wherein the light-splitting component is a first birefringent crystal or a polarization beam splitter and the light-combining component is a second birefringent crystal or a polarization beam combiner.

9. The optical depolarizer of claim 7 , wherein the delayer is a glass piece or a birefringent crystal.