Projector apparatus, projection method, and recording medium storing projection method

• US 20050046804A1
• Filed: 08/24/2004
• Published: 03/03/2005
• Est. Priority Date: 08/25/2003
• Status: Active Grant

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Akutsu, Takashi
• Granted Patent: US 7,222,971 B2
• Time in Patent Office: Days
• US Class Current: 353/70
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 9/3185 Geometric adjustment, e.g. keystone or convergence optical or mechanical adjustment of convergence H04N9/317; using scanning means H04N3/22; optical or mechanical adjustments of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H04N 9/3194 including sensor feedback

Abstract

A projector apparatus is disclosed which has a projection unit which projects image corresponding to an input image signal, an instruction unit which issues an instruction for performing keystone correction, a distance survey unit which surveys distances between the projector apparatus and a plurality of positions on the image projected by the projection unit in accordance with an instruction from the instruction unit, and a focus control unit which performs keystone correction of the image projected by the projection unit in a manner that the image becomes a rectangle having an appropriate aspect ratio based on the distances obtained by the distance survey unit, while bringing the image projected by the projection unit into focus at the center position of the image after being keystone-corrected.

Claims

1. A projector apparatus comprising:

a projection unit which projects an image corresponding to an input image signal;

an instruction unit which issues an instruction for performing keystone correction;

a distance survey unit which surveys a distance between the projector apparatus and each of a plurality of positions on the image projected by the projection unit, in accordance with an instruction from the instruction unit;

a keystone correction unit which performs keystone correction of the image projected by the projection unit, in a manner that the image becomes a rectangle having an appropriate aspect ratio based on distances obtained by the distance survey unit; and

a focus control unit which brings the image projected by the projection image into focus, at a center position of the image after being keystone-corrected by the keystone correction unit.

2. The projector apparatus according to claim 1,

wherein the focus control unit brings the image into focus based on a distance between the projector apparatus and the center position of the image after being keystone-corrected, which is obtained by the distance survey unit by re-surveying.

3. The projector apparatus according to claim 1,

wherein the focus control unit calculates a distance between the projector apparatus and the center position of the image after being keystone-corrected, based on the distances between the projector apparatus and the plurality of positions on the projected image, which distances are obtained by the distance survey unit.

4. The projector apparatus according to claim 1,

wherein the focus control unit brings the image into focus based on a distance between the projector apparatus and a position closest to the center position of the image after being keystone-corrected, the distance being selected from the distances between the projector apparatus and the plurality of positions on the projected image obtained by the distance survey unit.

5. The projector apparatus according to claim 1,

wherein the distance survey unit surveys distances between the projector apparatus and a plurality of positions on a chart image which is projected for distance survey.

6. The projector apparatus according to claim 5,

wherein the chart image projected for distance survey is constituted by a horizontal chart image for surveying distances between the projector apparatus and a plurality of positions in a horizontal direction, and a vertical chart image for surveying distances between the projector apparatus and a plurality of positions in a vertical direction.

7. A projection method comprising:

a projecting step of projecting an image corresponding to an input image signal;

an instructing step of issuing an instruction for performing keystone correction;

a distance surveying step of surveying distances between a projector apparatus and a plurality of positions on the image projected in the projecting step, in accordance with an instruction in the instructing step;

a keystone correcting step of performing keystone correction of the image projected in the projecting step, in a manner that the image becomes a rectangle having an appropriate aspect ratio, based on the distances obtained in the distance surveying step; and

a focus controlling step of bringing the image projected in the projecting step into focus, at a center position of the image after being keystone-corrected in the keystone correcting step.

8. The projection method according to claim 7,

wherein in the focus controlling step, the image is brought into focus based on a distance between the projector apparatus and the center position of the image after being keystone-corrected, which distance is obtained in the distance surveying step by re-surveying.

9. The projection method according to claim 7,

wherein in the focus controlling step, a distance between the projector apparatus and the center position of the image after being keystone-corrected is calculated based on the distances between the projector apparatus and the plurality of positions on the projected image obtained in the distance surveying step.

10. The projection method according to claim 7,

wherein in the focus controlling step, the image is brought into focus based on a distance between the projector apparatus and a position closest to the center position of the image after being keystone-corrected, the distance being selected from the distances between the projector apparatus and the plurality of positions obtained in the distance surveying step.

11. A recording medium storing a projection method which comprises:

a projecting step of projecting an image corresponding to an input image signal;

an instructing step of issuing an instruction for performing keystone correction;

a distance surveying step of surveying distances between a projector apparatus and a plurality of positions on the image projected in the projecting step, in accordance with an instruction in the instructing step;

a keystone correcting step of performing keystone correction of the image projected in the projecting step, in a manner that the image becomes a rectangle having an appropriate aspect ratio, based on the distances obtained in the distance surveying step; and

a focus controlling step of bringing the image projected in the projecting step into focus, at a center position of the image after being keystone-corrected in the keystone correcting step.

12. The recording medium storing the projection method according to claim 11,

wherein in the focus controlling step, the image is brought into focus based on a distance between the projector apparatus and the center position of the image after being keystone-corrected, which distance is obtained in the distance surveying step by re-surveying.

13. The recording medium storing the projection method according to claim 11,

wherein in the focus controlling step, a distance between the projector apparatus and the center position of the image after being keystone-corrected is calculated based on the distances between the projector apparatus and the plurality of positions on the projected image obtained in the distance surveying step.

14. The recording medium storing the projection method according to claim 11,

wherein in the focus controlling step, the image is brought into focus based on a distance between the projector apparatus and a position closest to the center position of the image after being keystone-corrected, the distance being selected from the distances between the projector apparatus and the plurality of positions obtained in the distance surveying step.