Lens module and projection device
AssigneeCoretronic Corporation
InventorChen-Wei Fan
Life of this patent
Estimating the term…
Abstract
The invention provides a lens module. The lens module is disposed on a transmission path of a beam to expand the beam. The lens module includes a first lens assembly and a second lens assembly. The first lens assembly is disposed on the transmission path of the beam, and the first lens assembly has a first equivalent focal length. The second lens assembly is disposed on the transmission path of the beam from the first lens assembly, and the second lens assembly has a second equivalent focal length. The second equivalent focal length is greater than or equal to the first equivalent focal length. The invention also provides a projection device including the lens module. The lens module and the projection device of the invention can provide a projection image with uniform color distribution.
Claims18
A lens module disposed on a transmission path of a beam and configured to expand the beam, the lens module comprising:
- a first lens assembly disposed on the transmission path of the beam, wherein the first lens assembly has a first equivalent focal length;
- a second lens assembly disposed on the transmission path of the beam from the first lens assembly, wherein the second lens assembly has a second equivalent focal length, and
- a diffusion element disposed on the transmission path of the beam from the first lens assembly, wherein the beam sequentially passes through the first lens assembly, the diffusion element, and the second lens assembly,
- wherein the second equivalent focal length is greater than or equal to the first equivalent focal length, wherein the beam travels a first optical path length between the first lens assembly and the diffusion element, and the first optical path length is equal to the first equivalent focal length.
A lens module disposed on a transmission path of a beam and configured to expand the beam, the lens module comprising:
- a first lens assembly disposed on the transmission path of the beam, wherein the first lens assembly has a first equivalent focal length;
- and
- a second lens assembly disposed on the transmission path of the beam from the first lens assembly, wherein the second lens assembly has a second equivalent focal length,
- wherein the second equivalent focal length is greater than or equal to the first equivalent focal length,
- wherein the beam travels a third optical path length between the first lens assembly and the second lens assembly, and the third optical path length is equal to a sum of the first equivalent focal length and the second equivalent focal length.
A projection device, comprising:
- an illumination system configured to provide an illumination beam, wherein the illumination system comprises:
- a light source module configured to emit the illumination beam;
- a lens module disposed on a transmission path of the illumination beam and configured to expand the illumination beam, wherein the lens module comprises:
- a first lens assembly disposed on the transmission path of the illumination beam and having a first equivalent focal length;
- a second lens assembly disposed on the transmission path of the illumination beam from the first lens assembly and having a second equivalent focal length, wherein the second equivalent focal length is greater than or equal to the first equivalent focal length;
- a diffusion element disposed on the transmission path of the illumination beam from the first lens assembly, wherein the illumination beam sequentially passes through the first lens assembly, the diffusion element, and the second lens assembly, wherein the illumination beam travels a first optical path length between the first lens assembly and the diffusion element, and the first optical path length is equal to the first equivalent focal length;
- and
- a light uniformizing element disposed on the transmission path of the illumination beam from the lens module;
- a light valve disposed on the transmission path of the illumination beam to modulate the illumination beam into an image beam;
- and
- a projection lens disposed on a transmission path of the image beam.
A projection device, comprising:
- an illumination system configured to provide an illumination beam, wherein the illumination system comprises:
- a light source module configured to emit the illumination beam;
- a lens module disposed on a transmission path of the illumination beam and configured to expand the illumination beam, wherein the lens module comprises:
- a first lens assembly disposed on the transmission path of the illumination beam and having a first equivalent focal length;
- and
- a second lens assembly disposed on the transmission path of the illumination beam from the first lens assembly and having a second equivalent focal length, wherein the second equivalent focal length is greater than or equal to the first equivalent focal length, wherein the illumination beam travels a third optical path length between the first lens assembly and the second lens assembly, and the third optical path length is equal to a sum of the first equivalent focal length and the second equivalent focal length;
- and
- a light uniformizing element disposed on the transmission path of the illumination beam from the lens module:
- a light valve disposed on the transmission path of the illumination beam to modulate the illumination beam into an image beam;
- and
- a projection lens disposed on a transmission path of the image beam.
Dependencies are inferred from the claim text.