ILLUMINATION LIGHT SOURCE DEVICE AND PROJECTOR PROVIDED WITH THE SAME, AND CONTROL METHOD OF THE PROJECTOR

• US 20140071182A1
• Filed: 08/28/2013
• Published: 03/13/2014
• Est. Priority Date: 09/10/2012
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Fujita, Kazuhiro, Takahashi, Tatsuya
• Granted Patent: US 9,250,506 B2
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: G02B 27/10 Beam splitting or combining systems polarising systems G02B27/28; mixing and splitting light signals using optical waveguides G02B6/28; beam shaping, e.g. changing the cross-sectional area, by dividing or superposing multiple light beams G02B27/0905
• CPC Class Codes: G03B 21/204 using secondary light emission, e.g. luminescence or fluorescence using different colours G03B33/00; if related to video signals H04N9/3197
• CPC Class Codes: G03B 21/2066 Reflectors in illumination beam in projection beam G03B21/28
• CPC Class Codes: G03B 33/08 Sequential recording or projection G03B33/02, G03B33/04, G03B33/06 take precedence

Abstract

An illumination light source device, comprising: a light path junction member which splits light emitted from a light source into a first light path emitting excitation light for phosphor and a second light path irradiating illumination light; a first diffuser disposed in the first light path; and a second diffuser disposed in the second light path, the second diffuser having a diffusion degree larger than that of the first diffuser.

Claims

1. An illumination light source device, comprising:

a light path junction member which splits light emitted from a light source into a first light path emitting excitation light for phosphor and a second light path irradiating illumination light;

a first diffuser disposed in the first light path; and

a second diffuser disposed in the second light path,

the second diffuser having a diffusion degree larger than that of the first diffuser.

2. An illumination light source device according to claim 1, further comprising:

a light path-combining element which combines the first and the second light paths;

the first diffuser having a first transmission/diffuser member which transmits and diffuses the excitation light towards a phosphor member; and

the second diffuser having a second transmission/diffuser member which transmits and diffuses the illumination light towards the light path-combining element.

3. An illumination light source device according to claim 1, wherein

the distance between the first transmission/diffuser member and the light path junction member is longer than that between the second transmission/diffuser member and the light path junction member.

4. An illumination light source device according to claim 2, wherein

a diffusion-angle of the first transmission/diffuser member is smaller than that of the second transmission/diffuser member.

5. An illumination light source device according to claim 2, wherein

the light path junction member includes a reflection/transmission wheel having a transmission area which transmits light from the light source and a reflection area which reflects light from the light source;

and

the reflection/transmission wheel is rotatably-driven.

6. An illumination light source device according to claim 2, wherein

the phosphor member includes a phosphor wheel which is rotatably-driven.

7. An illumination light source device according to claim 6, wherein

the phosphor wheel includes a disc-shaped base having a reflection member;

the phosphor is formed on the disc-shaped base in a ring-like shape; and

fluorescent light generated through an excitation light source is reflected by the disc-shaped base and directed to the light path-combining element.

16. A projector using the illumination light source device according to claim 1, comprising:

an irradiating light system which directs the illumination light emitted from the light path-combining element of the illumination light source device to an image generation part that generates a projection image;

a projecting light system which projects a projection image generated by the image generation part; and

a controller which divides a period of one frame of image data and controls the on/off control of the excitation light source in accordance with the image data and the image generation part, the controller being configured to generate the projection image corresponding to the image data using an after-image phenomenon of the eyes.

17. A projector according to claim 16, wherein the image generation part includes a digital micromirror device.

8. An illumination light source device, comprising:

a phosphor member including phosphor excited by excitation light from an excitation light source which is a part of an illumination optical system;

a reflection/transmission member disposed in an emitting light path of the excitation light source, the reflection/transmission member having a transmission area which transmits the excitation light from the excitation light source and a reflection area which reflects the excitation light, the reflection/transmission member configured to split the excitation light into a first light path where the excitation light passes through the phosphor member and a second light path where the excitation light does not pass through the phosphor member;

a driving part which drives the reflection/transmission member so that the emitting light path crosses the transmission area and the reflection area alternately;

a light path-combining element which combines the first and second light paths;

a first transmission/diffuser member disposed in the first light path, the first transmission/diffuser member being configured to transmit the excitation light and diffuse the excitation light towards the phosphor member; and

a second transmission/diffuser member disposed in the second light path, the second transmission/diffuser member being configured to transmit the excitation light from the excitation light source and diffuses the excitation light towards the light path-combining element, wherein

the distance between the first transmission/diffuser member and the reflection/transmission member is longer than that between the second transmission/diffuser member and the reflection/transmission member; and

the illumination optical system is comprised of a first illumination optical system provided in the emitting light path of the excitation light source of the reflection/transmission member and a second illumination optical system having an illumination light source which emits light of different wavelengths than those of the excitation light and the phosphor as illumination light.

9. An illumination light source device according to claim 8, wherein

a transmission/diffuser member is disposed in the emitting light path of the illumination light source of the second illumination optical system.

10. An illumination light source device according to claim 8, wherein

the first illumination optical system includes an optical element concentrating the excitation light from the excitation light source to form a spot area in the reflection/transmission member, and the optical element is driven towards the optical-axis direction so that a size of the spot area may be controlled.

11. An illumination light source device according to claim 8, wherein

the phosphor member includes a rotatably-driven phosphor wheel.

12. An illumination light source device according to claim 11, wherein

the illumination optical system includes only the first illumination optical system,

the phosphor is divided into at least a first semicircular arc phosphor and a second semicircular arc phosphor by a straight line that passes through the rotating center in the rotational direction of the phosphor;

and

each of the divided phosphors generates different colored fluorescent light to each other by the excitation light.

13. An illumination light source device according to claim 12, wherein

the excitation light source is a laser light source which emits a blue laser;

the first semicircular arc phosphor has a phosphor member excited by the excitation light and generates green fluorescence; and

the second semicircular arc phosphor has a phosphor member excited by the excitation light and generates red fluorescence.

14. An illumination light source device according to claim 12, wherein

the illumination optical system includes an optical element which concentrates the excitation light from the excitation light source and forms a spot area on the reflection/transmission member;

and

the optical element is driven towards the optical-axis direction so that the size of the spot area may be controlled.

15. An illumination light source device according to claim 8, wherein

a third transmission/diffuser member is provided in the light path where the excitation light does not pass through the phosphor member.

18. A method of controlling a projector including the illumination light source device according to claim 8, comprising the steps of:

driving the reflection/transmission member of the illumination light source device;

diffusing and directing the excitation light to the phosphor when the emitting light path passes the reflection area of the reflection/transmission member; and

diffusing and directing the excitation light to the light path-combining element when the emitting light path passes the transmission area of the reflection/transmission member.

19. A method of controlling a projector according to claim 18, further comprising the steps of:

detecting the position of the reflection/transmission member; and

controlling on/off of the light source calculating the timing of the reflection/transmission member crossing the emitting light path based on the detected result.

20. An illumination light source device, comprising:

a phosphor member including phosphor excited by excitation light from an excitation light source which is a part of an illumination optical system;

a reflection/transmission member disposed in an emitting light path of the excitation light source, the reflection/transmission member having a transmission area which transmits the excitation light from the excitation light source and a reflection area which reflects the excitation light, the reflection/transmission member configured to split the excitation light into a first light path where the excitation light passes through the phosphor member and a second light path where the excitation light does not pass through the phosphor member;

a driving part which drives the reflection/transmission member so that the emitting light path crosses the transmission area and the reflection area alternately;

a light path-combining element which combines the first and second light paths;

a first transmission/diffuser member disposed in the first light path, the first transmission/diffuser member being configured to transmit the excitation light and diffuse the excitation light towards the phosphor member; and

a second transmission/diffuser member disposed in the second light path, the second transmission/diffuser member being configured to transmit the excitation light from the excitation light source and diffuses the excitation light towards the light path-combining element, wherein

the diffusion-angle of the first transmission/diffuser member is smaller than that of the second transmission/diffuser member; and

the illumination optical system is comprised of a first illumination optical system provided in the emitting light path of the excitation light source of the reflection/transmission member and a second illumination optical system having an illumination light source which emits light of different wavelengths than those of the excitation light and the phosphor as illumination light.