Optical engine unit and projection system

Patent metadata

Field	Value
Publication number	US-12007677-B2
Application number	US-202017762424-A
Country	US
Kind code	B2
Filing date	Aug 31, 2020
Priority date	Sep 30, 2019
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

An optical engine unit and a projection system are provided. The optical engine unit includes a light splitting assembly, first and second spatial light modulators, and a light combining assembly. The light splitting assembly splits an illumination beam incident on the light splitting assembly into first and second light beams. The first and second spatial light modulators respectively modulate the first and second light beams to form first and second modulated light beams. The light combining apparatus includes a light combining surface. The light combining surface is a coated surface and configured to combine the first modulated light beam and the second modulated light beam into an emergent light beam and emit the emergent light beam. An incident angle of the first modulated light beam on the light combining surface and that of the second modulated light beam being smaller than a total reflection angle of the light combining surface.

First claim

What is claimed is:

1. An optical engine unit, comprising:
a light splitting assembly configured to split an illumination beam incident on the light splitting assembly into a first light beam and a second light beam;
a first spatial light modulator configured to modulate the first light beam to form a first modulated light beam;
a second spatial light modulator configured to modulate the second light beam to form a second modulated light beam; and
a light combining apparatus comprising a light combining surface, wherein the light combining surface is a coated surface and configured to combine the first modulated light beam and the second modulated light beam into an emergent light beam and emit the emergent light beam, and an incident angle of the first modulated light beam on the light combining surface and that of the second modulated light beam being smaller than a total reflection angle of the light combining surface.

2. The optical engine unit according to claim 1 , wherein the light combining apparatus comprises at least one totally reflective surface.

3. The optical engine unit according to claim 2 , wherein the first modulated light beam or the second modulated light beam enters the light combining surface after being reflected by the totally reflective surface.

4. The optical engine unit according to claim 3 , wherein an included angle formed between the light combining surface and the first spatial light modulator satisfies:
θ+α≤β,

where the illumination beam comprises a first edge light beam and a second edge light beam, θ representing an included angle formed between the first edge light beam and the second edge light beam, α representing the included angle between the light combining surface and the first spatial light modulator, and β representing the total reflection angle of the light combining surface.

5. The optical engine unit according to claim 1 , wherein the first light beam is parallel to the first spatial light modulator on an incident surface of the light combining apparatus, and the second light beam is parallel to the second spatial light modulator on the incident surface of the light combining apparatus.

6. The optical engine unit according to claim 1 , wherein the light combining apparatus at least comprises one triple prism and one cylindrical prism.

7. The optical engine unit according to claim 1 , wherein at least one of the first modulated light beam or the second modulated light beam enters the light combining surface after being reflected at least once in the light combining apparatus.

8. The optical engine unit according to claim 2 , further comprising:
a first guide assembly located at a side of the first spatial light modulator, wherein the first guide assembly is configured to guide the first light beam to the first spatial light modulator and guide the first modulated light beam to the light combining apparatus; and
a second guide assembly located at a side of the second spatial light modulator, wherein the second guide assembly is configured to guide the second light beam to the second spatial light modulator and guide the second modulated light beam to the light combining apparatus.

9. The optical engine unit according to claim 2 , wherein the light combining apparatus comprises a first prism and a second prism, wherein a light combining surface on which the first prism and the second prism join each other is opposite to a first totally reflective surface, being set on the first prism, wherein the second modulated light beam is reflected by the first totally reflective surface to the light combining surface, and the second prism is configured to guide the first modulated light beam to the light combining surface.

10. The optical engine unit according to claim 2 , wherein the light combining apparatus comprises:
a first prism,
a second prism, and
a third prism,
wherein the second prism is located between the first prism and the third prism; wherein the second modulated light beam is reflected by a third totally reflective surface on which the first prism and the second prism joining each other, to the light combining surface on which the second prism and the third prism joining each other, the third prism being configured to guide the first modulated light beam to the light combining surface, and the emergent light beam being emergent after being guided by the second prism and the first prism.

11. The optical engine unit according to claim 2 , wherein the light combining apparatus comprises:
a first prism, and
a second prism,
wherein the first prism further comprises a reflective surface opposite to the light combining surface on which the first prism and the second prism join each other, the second prism further comprises a second totally reflective surface opposite to the light combining surface, the second modulated light beam enters the light combining surface after being reflected by the light combining surface and the reflective surface sequentially, and the first modulated light beam is reflected by the second totally reflective surface to the light combining surface.

12. The optical engine unit according to claim 8 , wherein the first guide assembly comprises:
a first prism, and
a second prism,
wherein the first light beam is reflected to the first spatial light modulator by a third totally reflective surface on which the first prism and the second prism join each other; and
the second guide assembly comprises a third prism and a fourth prism, and the second light beam is reflected to the second spatial light modulator by a fourth totally reflective surface on which the third prism and the fourth prism join each other.

13. The optical engine unit according to claim 1 , wherein the light splitting assembly splits the illumination beam based on a characteristic of wavelength or polarization.

14. A projection system, comprising:
a light source; and
an optical engine unit, wherein the optical engine unit comprises:
a light splitting assembly configured to split an illumination beam incident on the light splitting assembly into a first light beam and a second light beam;
a first spatial light modulator configured to modulate the first light beam to form a first modulated light beam;
a second spatial light modulator configured to modulate the second light beam to form a second modulated light beam; and
a light combining apparatus comprising a light combining surface, wherein the light combining surface is a coated surface and configured to combine the first modulated light beam and the second modulated light beam into an emergent light beam and emit the emergent light beam, and an incident angle of the first modulated light beam on the light combining surface and that of the second modulated light beam being smaller than a total reflection angle of the light combining surface, and wherein the light source is configured to emit the illumination beam.

15. The projection system according to claim 14 , further comprising:
an optical relay system located between the light source and the light splitting assembly and configured to concentrate the illumination beam to a predetermined range.

16. The optical engine unit according to claim 4 , wherein, when θ=12° and β=42°, a critical angle of a glass prism is 42°, and α≤30°.

17. The optical engine unit according to claim 10 , wherein the fifth totally reflective surface is an anti-reflective coated surface, and reflectivity of the anti-reflective coated surface is smaller than a first preset threshold.

18. The optical engine unit according to

Assignees

• Appotronics Corp Ltd

Inventors

• Hu Fei
• Du Peng

Classifications

• G03B21/28

  Reflectors in projection beam {(in illumination beam G03B21/2066)} · CPC title

• G03B21/005

  Projectors using an electronic spatial light modulator but not peculiar thereto · CPC title

• G03B21/2066 Primary

  Reflectors in illumination beam (in projection beam G03B21/28) · CPC title

• G03B21/20 Primary

  Lamp housings · CPC title