JP2005084100A - Projector having focusing mechanism and diaphragm adjustment mechanism and method for forcibly opening diaphragm - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector which has a mechanism for automatically opening a diaphragm when a projection lens is focused and projects an image onto a projection screen. <P>SOLUTION: The projector includes: an optical diaphragm mechanism 22 having a forcible opening mechanism which opens the diaphragm from a set diaphragm position to a diaphragm open position for a predetermined length of time; a focusing operation detection part 44 which detects the focusing operation of a projection lens 21; a diaphragm forcibly opening part 45 which operates the forcible opening mechanism of the optical diaphragm adjustment mechanism 22 upon the detection of the focusing operation by the focusing operation detection part 44; and a timer 46 which sets the operation time of the forcible opening mechanism. When the focusing operation detection part 44 detects the focusing operation of the projection lens 21, the diaphragm forcibly opening part 45 operates the forcible opening mechanism of the optical diaphragm mechanism 22 and opens the diaphragm only for a predetermined time. Thus, the focusing operation is performed with the open diaphragm of a narrow focal depth, and a stable, satisfactory image can be obtained on the projection screen. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a projector, and more particularly to a method for forcibly opening an aperture of a projector having a focus adjustment mechanism and an aperture adjustment mechanism.

  With the rapid development of liquid crystal technology and DLP (registered trademark) (digital light processing) technology, miniaturization and high performance of projectors have expanded the use of projectors for image projection, and display televisions at home. It is also attracting attention as a large-sized display device that can replace this.

  However, unlike a display-type television, the image plane is a screen or a wall. Therefore, it is necessary to adjust the focal point so that the image is clearly formed on the projection plane every time the projector is installed. Normally, the focus is manually adjusted while watching the screen image. However, since manual adjustment is complicated, automatic focus adjustment has also been proposed. The projection lens has a focus adjustment mechanism, and a movable transmissive reflector is provided between the light source and the projection lens. In the focus adjustment mode, the movable transmissive reflector is positioned between the light source and the projection lens to reflect light from the screen. An autofocus device for a liquid crystal projector is disclosed in which a light receiving element at a position equivalent to a light source is received and a focus position is detected and calculated by a light reception output signal to control a focus adjustment mechanism (see, for example, Patent Document 1).

In addition, recently, an optical diaphragm mechanism for narrowing the cross section of the optical path in order to enhance the contrast of the display image, reduce the optical aberration, or increase the depth of focus has come to be performed. The diaphragm adjustment in the optical diaphragm mechanism is usually performed manually (see, for example, Patent Document 2).
Japanese Patent Application Laid-Open No. 11-1198185 JP 2002-72361 A

  The image quality of the image on the projection surface is improved by performing both the focus adjustment and the aperture adjustment, but the focus depth increases when the focus adjustment is performed while the aperture adjustment is in progress, so the focus distance is increased. There was a problem that it spreads out and adjustment in an optimal state becomes difficult.

  FIGS. 3A and 3B are schematic views showing the image formation state of the projection light from the projector on the projection surface, where FIG. 3A is a state where the aperture of the optical aperture mechanism is open, and FIG. 3B is an aperture state of the optical aperture mechanism. This case is shown. The projection light 28 from the unit light emitting unit 23 a of the display unit 23 that has passed through the opening of the inner optical aperture mechanism 22 is condensed by the focus-adjusted projection lens 21 to form a focal point 29 on the projection surface 70. .

  The projected light 28 projected from the unit light emitting unit 23a (single pixel) of the display unit 23 is preferably focused on the projection surface 70 so that the image projected on the projection surface 70 can be clearly seen one pixel at a time. When the aperture of the optical aperture mechanism shown in FIG. 3A is in the open state, the focus is set in the range of the depth of field 25, but when the aperture of the optical aperture mechanism shown in FIG. Is focused in a range of a depth of field 25 ′ wider than the depth of field 25. In this case, when the focus adjustment of the projection lens 21 is performed, it seems that the focus is formed anywhere in the range of the depth of field 25 ′. However, if a change in projection conditions is taken into consideration, the focus is adjusted to a position close to the center of this range. When the aperture of the optical aperture mechanism in FIG. 3A is in the open state, the range of the depth of field 25 is narrow and close to the desired state.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a projector with an aperture opening mechanism at the time of focus adjustment, which has a mechanism that automatically opens an aperture when adjusting the focus of a projection lens in a projector that projects an image on a projection surface.

The projector having the focus adjustment mechanism and the aperture adjustment mechanism of the present invention,
An optical diaphragm mechanism having a diaphragm adjusting mechanism having a forced opening mechanism that can be opened from a set diaphragm position to a diaphragm opening position for a predetermined time;
A focus adjustment operation detector for detecting a focus adjustment operation of a projection lens having a focus adjustment mechanism;
When the focus adjustment operation detection unit detects the focus adjustment operation, a forced aperture opening unit that operates the forced opening mechanism,
A timer used to set the operation time of the forced release mechanism,
When the focus adjustment operation detection unit detects the focus adjustment operation of the projection lens, the forcible aperture opening unit operates the forcible opening mechanism of the aperture adjustment mechanism to open the aperture for a predetermined time.

  The present invention has the effect that the focal length of the projection lens of a projector having an aperture adjustment mechanism can be adjusted within a narrow focal depth range, and a stable and good image can be obtained. This is because the focal length is adjusted in a state where the aperture is automatically opened and the depth of focus is narrowed when the focus of the projection lens is adjusted.

  In the present invention, in a projector having a focus adjustment mechanism and an aperture adjustment mechanism, an optical aperture mechanism provided with an aperture adjustment mechanism having a forcible opening mechanism that can be opened from a set aperture position to an aperture opening position for a predetermined time; , A focus adjustment operation detection unit that detects the focus adjustment operation of the projection lens, an aperture forced release unit that operates the forced opening mechanism of the aperture adjustment mechanism when the focus adjustment operation detection unit detects the focus adjustment operation, and the operation of the forced release mechanism And a timer for setting the time, and when the focus adjustment operation detection unit detects the focus adjustment operation of the projection lens, the aperture forcible opening unit operates the forcible opening mechanism of the aperture adjustment mechanism to open the aperture for a predetermined time. As a result, the focus adjustment operation is performed with the aperture having a narrow focal depth open, and a stable and good image can be obtained on the projection surface.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram of a projector having a focus adjustment mechanism and a diaphragm adjustment mechanism according to the first embodiment of the present invention.

  The projector 10 includes a projection device 21 having an adjustable focal length, an optical aperture mechanism 22 having a forcible opening mechanism, and a display unit 23, an image control unit 30 for controlling an image on the display unit 23, and focus / aperture control. A unit 40 and a CPU 60 for controlling the overall operation are provided.

  The focus / aperture control unit 40 includes a focus adjustment unit 41 that adjusts the focal length of the projection lens 21, a focus operation unit 42 that operates the focal length, a diaphragm operation unit 43 that operates the aperture of the optical aperture mechanism 22, A focus adjustment operation detection unit 44 that detects the operation of the focus adjustment unit 41, and a diaphragm by a forcible opening mechanism of the optical aperture mechanism 22 in which the aperture is set when the focus adjustment operation detection unit 44 detects the operation of the focus adjustment unit 41. When the set time elapses after detecting the end of the adjustment operation of the focus adjustment unit 41 by operating the degree to the open state, the aperture forced opening unit 45 that returns to the set aperture degree, and the focus adjustment unit 41 And a timer 43 that sets a time period from the detection of the end of the adjustment operation to the return to the set aperture value.

  Here, the time to return to the forced opening of the aperture is assumed to be until a set time elapses after the end of the adjustment operation of the focus adjustment unit 41 is detected, but the set time after the forcible opening elapses. You may do it.

  Further, the focus adjustment may be performed by manual operation of the focus operation unit 42, or may be performed by an automatic focus adjustment signal input to the focus operation unit 42 by an automatic distance measurement mechanism or a projection screen analysis mechanism. it can.

  Next, a method for forcibly opening the aperture in the projector having the focus adjustment mechanism and the aperture adjustment mechanism of the present invention will be described. FIG. 2 is a flowchart of a method for forcibly opening the aperture of the projector having the focus adjustment mechanism and the aperture adjustment mechanism of the present invention.

  When processing by the forced aperture opening method is started, the focus adjustment operation detection unit 44 monitors the focus adjustment operation in the focus adjustment unit 41 (step S1N), and when the focus adjustment operation in the focus adjustment unit 41 is started (step S1Y). The aperture forcible opening unit 45 forcibly opens the aperture of the aperture level set by the aperture operation unit 43 in the optical aperture mechanism 22 (step S2), and the focus adjustment operation detection unit 44 adjusts the focus in the focus adjustment unit 41. The end of the operation is monitored (step S3N). When the end of the focus adjustment operation is confirmed (step S3Y), the timer 46 is started (step S4N), and when the set time of the timer 46 ends (step S5Y), the aperture The forcible opening unit 45 restores the aperture that is forcibly opened by the optical aperture mechanism to the aperture level that was set before the aperture was opened (step by step). Flop S6), if not the process ends (step S7: NO), processing continues back to step S1, if the processing is finished (step S7Y), and ends the process of squeezing force open method.

1 is a schematic block configuration diagram of a projector having a focus adjustment mechanism and a diaphragm adjustment mechanism according to a first embodiment of the present invention. 6 is a flowchart of a method for forcibly opening an aperture of a projector having a focus adjustment mechanism and an aperture adjustment mechanism according to the present invention. It is a schematic diagram which shows the image formation state in the projection surface of the projection light from a projector. (A) shows the case where the aperture of the optical aperture mechanism is open. (B) shows the case where the aperture of the optical aperture mechanism is in the aperture state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Projector 20 Projection apparatus 21 Projection lens 22 Optical aperture mechanism 23 Display part 23a Unit light emission part 25, 25 'Depth of field 27 Optical axis 28 Projection light 29 Focus 30 Image control part 40 Focus / aperture control part 41 Focus adjustment part 42 Focus operation unit 43 Aperture operation unit 44 Focus adjustment operation detection unit 45 Aperture forced opening unit 46 Timer 60 CPU
70, 70 'projection surface

Claims (6)

In a projector having a focus adjustment mechanism and a diaphragm adjustment mechanism of a projection lens,
The aperture adjustment mechanism having a forced opening mechanism capable of opening from a set aperture position to an aperture opening position for a predetermined time; and
A focus adjustment operation detector for detecting a focus adjustment operation of the projection lens having the focus adjustment mechanism;
When the focus adjustment operation detection unit detects a focus adjustment operation, an aperture forced opening unit that operates the forced opening mechanism;
A timer used for setting an operation time of the forced release mechanism,
When the focus adjustment operation detection unit detects a focus adjustment operation of the projection lens, the aperture forcible opening unit operates the forcible opening mechanism of the aperture adjustment mechanism to open the aperture for a predetermined time. A projector having an adjustment mechanism and an aperture adjustment mechanism. The projector includes a projection device, an image control unit, a focus / aperture control unit, and a CPU.
The projection device includes a projection lens having the focus adjustment mechanism, an optical diaphragm mechanism having the diaphragm adjustment mechanism for performing a diaphragm of incident light of the projection lens, and a display for projecting an image by control of the image control unit. And
The focus / aperture control unit includes a focus operation unit and a focus adjustment unit that control the focus adjustment mechanism, the focus adjustment operation detection unit, the aperture forced opening unit, the timer, and an aperture of the optical aperture mechanism. The projector having the focus adjustment mechanism and the aperture adjustment mechanism according to claim 1, further comprising an aperture operation unit that operates the degree.   The projector having the focus adjustment mechanism and the aperture adjustment mechanism according to claim 1, wherein a predetermined opening time of the aperture by the aperture forced opening unit is a set time of the timer.   The predetermined aperture opening time by the aperture forced opening unit is determined by the focus adjustment operation detection unit after the focus adjustment operation detection unit detects the focus adjustment operation of the projection lens and operates the forced opening mechanism. The projector having the focus adjustment mechanism and the aperture adjustment mechanism according to claim 1 or 2, wherein the time is the time until the end of the timer that is started by detecting the end of the focus adjustment operation of the projection lens. A method for forcibly opening an aperture during focus adjustment in a projector having the focus adjustment mechanism and the aperture adjustment mechanism according to any one of claims 1 to 4,
A step of the focus adjustment operation detection unit monitoring the focus adjustment operation in the focus adjustment unit;
A step of forcibly opening the aperture of the aperture set by the aperture operation unit in the optical aperture mechanism when the focus adjustment operation detection unit detects a focus adjustment operation in the focus adjustment unit;
A step to start a timer;
When the set time of the timer ends, the forced aperture opening unit returns the aperture that is forcibly opened by the optical aperture mechanism to the aperture level that was set before the aperture was opened.   6. The aperture stop according to claim 5, further comprising: before the step of starting the timer, the focus adjustment operation detecting unit monitoring the end of the focus adjustment operation in the focus adjustment unit and confirming the end of the focus adjustment operation. Forced release method.

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