JP2021057641A - projector - Google Patents

Abstract

To provide a projector that makes it possible to reduce the deterioration of image quality when trapezoidal distortion of a projected image is corrected.SOLUTION: A projector includes inclination amount detecting means that detects the inclination amount in the projection direction, lens tilt means that changes the projection direction, lens tilt driving means that drives the lens tilt, lens tilt amount detecting means that detects the lens tilt amount, and lens tilt control means, and the lens tilt control means controls the lens tilt depending on the tilt amount detecting result so as to correct the distortion of a projected image by the lens tilt driving means and the lens tilt amount detecting means.SELECTED DRAWING: Figure 1

Description

The present invention relates to a projector, and more particularly to a distortion correction of a projected image that occurs when the projection direction of the projector is obliquely upward or diagonally downward.

Conventionally, when the projected image is projected diagonally upward or diagonally downward with respect to the screen, the projected image is distorted into a trapezoid. Therefore, a technique is known in which the projected image is corrected to a rectangular shape by reversely deforming the image by image processing.

Patent Document 1 discloses a technique of detecting the inclination of the projection type image device in the projection direction and correcting the tilt distortion due to the inclination of the projection type display device with respect to the screen screen by image processing.

Japanese Unexamined Patent Publication No. 10-11533

However, in the conventional technique disclosed in Patent Document 1 described above, since the image is deformed by image processing, the resolution is lowered and the image quality is lowered.

Therefore, an object of the present invention is to provide a projector capable of reducing image quality deterioration when correcting trapezoidal distortion of a projected image.

In order to achieve the above object, the projector according to the present invention
An inclination amount detecting means for detecting the inclination amount in the projection direction, and
Lens tilt means to change the projection direction and
Lens tilt driving means for driving the lens tilt,
Lens tilt amount detecting means for detecting the lens tilt amount, and
Lens tilt control means and
Is a projector with
The lens tilt control means controls the lens tilt so as to correct the distortion of the projected image by the lens tilt driving means and the lens tilt amount detecting means according to the tilt amount detection result.

According to the present invention, it is possible to provide a projector capable of reducing image quality deterioration when correcting trapezoidal distortion of a projected image.

Block diagram of feasibility 1 of the present invention Flowchart of feasibility 1 of the present invention Block diagram of the case where the interchangeable lens with the lens tilt function of the feasibility 2 of the present invention is attached Block diagram of the case where the interchangeable lens without the lens tilt function of the second embodiment of the present invention is attached. Flowchart of feasibility 2 of the present invention

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram according to an embodiment of the present invention.

Hereinafter, a block diagram of a first embodiment of the present invention will be described with reference to FIG.

The image signal input unit 101 includes an interface connector for image signal input, and an image signal is input from the outside. The input image signal is output to the image signal processing unit 102.

The image signal processing unit 102 performs various signal processing such as image correction such as scaling, brightness correction, contrast correction, and color correction. Further, the image signal processing unit 102 calculates the distortion correction amount of the projected image by the image processing described in detail later, and also performs the distortion correction by the image signal processing based on the calculation result. The image signal processed by the image signal processing unit 102 is output to the liquid crystal panel driving unit 103.

The liquid crystal panel driving unit 103 drives the liquid crystal panel 104 based on the input image signal. The liquid crystal panel may be a transmissive type or a reflective type, or a display element other than the liquid crystal panel may be used.

On the other hand, the light emitted from the light source 105 is image-modulated by the liquid crystal panel 104 and projected onto the screen or the like by the projection lens 106.

The MPU 107 controls each part of the projector. The MPU 107 outputs a light source control command to the light source driving unit 108, so that the light source driving unit 108 drives the light source such as turning on / off the light source 105 and dimming.

The lens tilt mechanism 109 is a mechanism for changing the projection direction. The MPU 107 can drive the lens tilt mechanism 109 by outputting a lens tilt control command to the lens tilt drive unit 110. Further, a lens tilt amount detection unit 111 for detecting the lens tilt amount is provided, and the lens tilt amount detection result is output to the MPU 107. That is, the MPU 107 can perform feedback control by issuing a control command to the lens tilt drive unit 110 while detecting the lens tilt amount. The lens tilt drive unit 110 may be a DC motor, a stepping motor, or another actuator. The lens tilt amount detection unit 111 may be an optical encoder, a magnetic encoder, or an encoder of another type. Further, even if it is not an encoder, a method of acquiring an absolute value using a variable resistor may be used.

The tilt amount detection unit 112 detects the tilt amount of the projector body (in the projection direction when the lens is not tilted), and outputs the result to the MPU 107. The tilt amount detection unit 112 may be any as long as it can detect the tilt amount of the projector main body such as an acceleration sensor.

The operation unit 113 reads the input user operation by the MPU 107 and performs an operation according to the operation.

When the distortion correction of the projected image is generated by the user operation, the MPU 107 acquires the tilt amount from the tilt amount detection unit 112 and performs lens tilt control according to the tilt amount. When the lens tilt amount of the MPU 107 reaches the drive limit and the distortion of the projected image cannot be corrected by the lens tilt, the MPU 107 outputs the tilt amount and the lens tilt amount to the image signal processing unit 102, and the image signal processing unit 102 inputs the tilt amount and the lens tilt amount. The amount of distortion correction of the projected image by image processing is calculated according to the amount of tilt and the amount of lens tilt, and the distortion is corrected by image processing based on the calculation result.

This concludes the description of the block diagram of the first embodiment of the present invention.

Subsequently, the flowchart of the first embodiment of the present invention will be described with reference to FIG.

In step 101 (denoted as S in the figure) 101, it is determined whether or not there is a distortion correction instruction from the user. If there is no instruction, the process returns to step 101, and if there is an instruction, the process proceeds to step 102.

In step 102, the tilt amount is acquired from the tilt amount detection unit 112.

In step 103, the target value of the lens tilt amount according to the detected tilt amount is calculated.

In step 104, the lens tilt amount is detected and it is determined whether or not the target value has been reached. If the target value has been reached, the flow chart is terminated assuming that the distortion correction is completed, and if the target value has not been reached, the process proceeds to step 105.

In step 105, it is determined whether or not the detected lens tilt amount has reached the drive limit. If it has not been reached, the process proceeds to step 106, and if it has been reached, the process proceeds to step 107.

In step 106, the lens tilt drive is performed toward the lens tilt target value, and the process returns to step 104.

In step 107, the correction amount of the distortion correction performed in the image processing is calculated from the tilt amount and the lens tilt amount.

In step 108, distortion correction is performed by image processing, and the flowchart is terminated on the assumption that the distortion correction is completed.

This concludes the description of the flowchart of the first embodiment of the present invention.

Hereinafter, a block diagram of a second embodiment of the present invention will be described with reference to FIGS. 3 and 4.

The same reference numerals are given to the same configurations as in Example 1 of the present invention, and detailed description thereof will be omitted.

In the second embodiment of the present invention, the projector is composed of a projector main body 10 and an interchangeable lens unit. As the types of interchangeable lens units, there are one or more types having a lens tilt function and one or more types having no lens tilt function.

FIG. 3 is a block diagram when an interchangeable lens unit 20a having a lens tilt function is attached to the projector main body 10, and FIG. 4 is a block diagram when an interchangeable lens unit 20b without a lens tilt function is attached to the projector main body 10. is there.

The lens function storage unit 201 is a storage unit for storing the lens function, and specifically, stores the presence / absence of the lens tilt function. The MPU 107 can read the presence / absence of the lens tilt function from the lens function storage unit 201, and by reading the presence / absence of the lens tilt function, it can be determined whether or not the mounted interchangeable lens unit has the lens tilt function. When distortion correction of the projected image occurs by user operation, distortion correction is performed by the lens tilt function when an interchangeable lens unit having a lens tilt function is attached in order to reduce the deterioration of image quality. If an interchangeable lens unit that does not have a lens tilt function is installed, distortion is corrected by image processing.

This concludes the description of the block diagram of the second embodiment of the present invention.

Subsequently, the flowchart of the second embodiment of the present invention will be described with reference to FIG.

In step 201 (denoted as S in the figure) 201, it is determined whether or not there is a distortion correction instruction from the user. If there is no instruction, the process returns to step 201, and if there is an instruction, the process proceeds to step 202.

In step 202, the tilt amount is acquired from the tilt amount detection unit 112.

In step 203, it is confirmed whether or not the interchangeable lens unit mounted from the lens function storage unit 201 has a lens tilt function. If there is a lens tilt function, the process proceeds to step 204, and if there is no lens tilt function, the process proceeds to step 210.

In step 204, the target value of the lens tilt amount according to the detected tilt amount is calculated.

In step 205, the lens tilt amount is detected and it is determined whether or not the target value has been reached. If the target value has been reached, the flow chart is terminated assuming that the distortion correction is completed, and if the target value has not been reached, the process proceeds to step 206.

In step 206, it is determined whether or not the detected lens tilt amount has reached the drive limit. If it has not been reached, the process proceeds to step 207, and if it has been reached, the process proceeds to step 208.

In step 207, the lens tilt drive is performed toward the lens tilt target value, and the process returns to step 205.

In step 208, the correction amount of the distortion correction performed in the image processing is calculated from the tilt amount and the lens tilt amount.

In step 209, distortion correction is performed by image processing, and the flowchart is terminated on the assumption that the distortion correction is completed.

In step 210, the correction amount of the distortion correction performed by the image processing is calculated from the inclination amount.

In step 211, distortion correction is performed by image processing, and the flowchart is terminated on the assumption that the distortion correction is completed.

This concludes the description of the flowchart of the second embodiment of the present invention.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and modifications can be made within the scope of the gist thereof.

109 lens tilt means, 110 lens tilt drive means,
111 Lens tilt amount detecting means, 112 Tilt amount detecting means

Claims (3)

An inclination amount detecting means for detecting the inclination amount in the projection direction, and
Lens tilt means to change the projection direction and
Lens tilt driving means for driving the lens tilt,
Lens tilt amount detecting means for detecting the lens tilt amount, and
Lens tilt control means and
Is a projector with
A projector characterized in that the lens tilt control means controls the lens tilt so as to correct the distortion of the projected image by the lens tilt driving means and the lens tilt amount detecting means according to the tilt amount detection result. Further, a distortion correction amount calculation means for calculating the distortion correction amount of the projected image by image processing, and
Distortion correction amount If the lens tilt amount reaches the drive limit and the distortion correction of the projected image by the lens tilt cannot be performed, the tilt amount has a distortion correction means that corrects the distortion of the projected image by image processing according to the calculation result of the distortion correction amount. The projector according to claim 1, wherein the distortion correction amount is calculated according to the detection result and the lens tilt amount, and the distortion of the projected image is corrected by the distortion correction means by image processing. In an interchangeable lens type projector, the types of interchangeable lenses include one or more types of lenses having a lens tilt function and one or more types of lenses not having a lens tilt function.
Lens function storage means for memorizing the presence / absence of the lens tilt function,
An inclination amount detecting means for detecting the inclination amount in the projection direction, and
Lens tilt control means and
Distortion correction amount calculation means for calculating the distortion correction amount of the projected image by image processing,
Distortion correction amount Distortion correction means that corrects the distortion of the projected image by image processing according to the calculation result,
Have,
Furthermore, lenses with a lens tilt function include a lens tilt means for changing the projection direction, a lens tilt drive means for driving the lens tilt, and a lens tilt drive means for driving the lens tilt.
Lens tilt amount detecting means for detecting the lens tilt amount, and
Have,
Read the presence / absence of the lens tilt function stored in the lens function storage means,
When the lens tilt function is provided, the lens tilt control means controls the lens tilt so as to correct the distortion of the projected image by the lens tilt drive means and the lens tilt amount detection means according to the tilt amount detection result.
When there is no lens tilt function, the projector is characterized in that the distortion correction amount is calculated according to the tilt amount detection result, and the distortion of the projected image is corrected by the distortion correction means by image processing.

Images