WO2019179080A1

WO2019179080A1 - Device and method for adjusting projected image

Info

Publication number: WO2019179080A1
Application number: PCT/CN2018/110328
Authority: WO
Inventors: 朱红亮; 韩运起; 谢颂婷; 李屹
Original assignee: 深圳光峰科技股份有限公司
Priority date: 2018-03-20
Filing date: 2018-10-16
Publication date: 2019-09-26
Also published as: CN110312108B; CN110312108A

Abstract

Disclosed are a device and method for adjusting a projected image. The device for adjusting a projected image comprises: a projection lens used to project an image; multiple projected light determination units provided at respective top corners of a specified projection region, the multiple projected light determination units being used to receive ambient light and projected light and to generate and transmit control information on the basis of types of received light; and a control unit sequentially receiving the control information transmitted by the respective projected light determination units and adjusting the projection lens according to the control information. The present invention employs a light sensing apparatus to realize automatic adjustment and correction of a projected image, thereby shortening a time period required for adjusting an area and a position of a projected image, and increasing adjustment precision.

Description

Projection image adjusting device and method

Technical field

The present invention relates to the field of optical imaging, and more particularly to a projection image adjusting apparatus and method.

Background technique

Currently, projection products are widely used in various applications such as movie broadcasting, conferences, and publicity. For commercially available projection products, usually, after the after-sales personnel install the projection device and the screen, it is necessary to manually perform the zooming of the lens manually by a control device such as a remote controller. For example, first, a preliminary judgment is made by the naked eye, that is, whether the projected area on the screen is substantially the same as the projected area required by the user, and the projected area is manually scaled if the projected area does not meet the user's needs. Then, after the projected area substantially conforms to the user's needs, the projected position is manually moved to a prescribed projection position desired by the user. In this projection position adjustment process, there are often a large amount of deviation. This requires further lens zooming until the projection appears at the projection position desired by the user.

Further, if there is a deviation at any of the four corners of the up, down, left, and right (for example, a case where the projected image is trapezoidal), it is necessary to further adjust the projected image to adjust the projection position. It can be seen that in the actual use of the existing products, it is necessary to alternately perform at least three processes of lens zooming, lens shifting, and lens image adjustment. In this case, the adjustment cycle is quite time consuming, and the projection position adjustment takes up to 80% of the time throughout the after-sales service. However, the final adjustment results can only barely reach the projected position of the user's needs.

In summary, the projection position adjustment process has a long cycle and is not highly accurate. In addition, for the existing projection products, if the late lens has an unexpected offset that the user cannot handle, it is necessary to specially arrange the after-sales personnel to handle such problems. This can consume a lot of manpower and time costs.

Summary of the invention

Accordingly, it is an object of the present invention to provide a projection adjustment apparatus and method capable of automatically adjusting a projected image to solve the problem that the projection position adjustment process existing in the prior art has a long period and low precision.

In order to solve the above problems, the present invention provides a projection image adjusting device including: a projection lens for projecting an image; a plurality of projection light determining units, each of the plurality of projection light determining units being disposed at a designated projection area a top corner portion, and each of the plurality of projection light determining units is configured to receive ambient light and projection light, and generate and transmit control information based on the type of the received light; and a control unit that sequentially receives The control information transmitted by each of the projection light determination units adjusts the projection lens based on the control information.

Each of the plurality of projection light determination units may include a first signal receiving portion and at least two second signal receiving portions for receiving ambient light and projection light, wherein the projection is set at the top corner portion The light determining unit, the first signal receiving portion is arranged closer to a geometric center of the designated projection area than the at least two second signal receiving portions; and a determining portion, the determining portion determining the Whether the ambient light or the projection light is received by each of the first signal receiving portion and the at least two second signal receiving portions, and when the intensity of the received light is greater than a threshold, determining that the projected light is When the intensity of the received light is equal to or smaller than the threshold, it is determined that the ambient light is generated, and the corresponding control information is generated.

Preferably, the at least two second signal receiving portions are disposed at least on two straight lines: the two straight lines pass through the first signal receiving portion and respectively form the projection region forming the apex portion The two sides are parallel.

Preferably, when it is determined that, in one of the projection light determining units, the projection light determining unit receives at least one of the second signal receiving units, the control unit controls based on the control information The projection lens moves and/or reduces the projection image toward the first signal receiving portion of the projection light determining unit until only the first signal receiving portion receives the projection light.

Preferably, when it is determined that none of the first signal receiving portion and all of the second signal receiving portions in one of the projection light determining units receives the projection light, the control unit controls based on the control signal The projection lens moves and/or enlarges the projected image until the projected light determining unit receives the projected light signal.

Preferably, in each of the projection light determining units, when only the first signal receiving portion closest to the geometric center receives the projected light signal, the projected image adjusting device completes the adjustment of the projected image.

Preferably, the shape of the specified projection area is a regular polygon or an irregular polygon, wherein when the shape of the specified projection area is the irregular polygon, the geometric center is a geometric center of gravity, and the geometric center of gravity is located The inside of the irregular polygon.

According to another aspect of the present invention, there is further provided a projection image adjusting method comprising the steps of: arranging a plurality of projection light determining units at respective vertex portions of a designated projection area, and projecting an image with the projection lens; Each of the plurality of projection light determination units receives the ambient light and the projection light, and generates and transmits the control information based on the type of the received light; and sequentially receives the control information transmitted by each of the projection light determination units by the control unit And adjusting the projection lens based on the control information.

Preferably, each of the plurality of projection light determination units includes: a first signal receiving portion for receiving ambient light and projection light, and at least two second signal receiving portions, wherein when set at the top corner portion The projection light determining unit, the first signal receiving portion is disposed closer to a geometric center of the designated projection region than the at least two second signal receiving portions; and a determining portion, the determining portion Determining whether each of the first signal receiving unit and the at least two second signal receiving units receives the ambient light or the projection light, and when the intensity of the received light is greater than a threshold, determining that the projection is Light, when the intensity of the received light is equal to or less than the threshold, determines that the ambient light is, and generates corresponding control information.

According to the present invention, a projection light determining unit is installed at each vertex of the designated projection area, the projection light determining unit transmits the control information according to the received signal, and the control unit receives the control information to adjust parameters such as the position and size of the projected image, Thus, when the projection system having the projection image adjusting device according to the present invention is used, the projected image can be automatically and quickly adjusted to a position desired by the user.

DRAWINGS

Fig. 1 shows a schematic block diagram of a projection image adjusting device according to an embodiment of the present invention.

Fig. 2 shows an arrangement example of a projection light determination unit according to an embodiment of the present invention.

Fig. 3 shows an arrangement example of a signal receiving portion in a projection light determining unit according to an embodiment of the present invention.

4 shows a flow chart of a projection image adjustment method in accordance with one embodiment of the present invention.

FIG. 5 shows an arrangement example of a projection light determination unit according to another embodiment of the present invention.

Fig. 6 shows a detailed configuration of the broken line portion of Fig. 5.

detailed description

Hereinafter, a projection image adjusting device and method according to the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 shows a block diagram of a projection image adjusting device according to an embodiment of the present invention.

As shown in FIG. 1, a projection image adjusting device according to an embodiment of the present invention includes a projection lens, a projection light determination unit, and a control unit. In actual operation, the projection lens projects a projected image, and the object of the present invention is to project an image to a designated projection area and automatically adjust the size of the projected image to match the projected image with the designated projection area. In the present embodiment, the designated projection area is preferably a rectangular screen. It can be understood that in the embodiment, the specified projection area shape may be any regular polygon desired by the user.

As shown in FIG. 2, the projection light determining units A, B, C, and D are respectively disposed at the four vertex angles of the rectangular screen, that is, the projection light determining unit A in the upper left corner, the projection light determining unit B in the upper right corner, and the lower left side. The angled projection light determination unit C and the lower right corner projection light determination unit D. Preferably, after the projection system is activated, the projection light determining units A, B, C, D are for receiving ambient light and projection light, and generating and transmitting control information based on the kind of the received light.

According to the present invention, each of the projection light determination units includes a first signal receiving portion for receiving ambient light and projection light and at least two second signal receiving portions, wherein when the projection light determining unit is disposed at the vertex portion, Arranging the first signal receiving portion to be closer to a geometric center of the designated projection area than the at least two second signal receiving portions, and the at least two second signal receiving portions are disposed at least on two straight lines: two straight lines Each passing through the first signal receiving portion and respectively parallel to two sides of the projection area forming the vertex portion; and a judging portion determining that each of the first signal receiving portion and the at least two second signal receiving portions receives The ambient light is also projection light. When the intensity of the received light is greater than the threshold, it is determined to be projection light. When the intensity of the received light is equal to or smaller than the threshold, it is determined to be ambient light, and corresponding control information is generated.

Although the ambient light signal is used as the threshold in the present embodiment, it should be noted that the threshold is not limited to the ambient light signal, and the threshold may be freely set by the user.

Fig. 3 shows an arrangement example of a signal receiving portion in a projection light judging unit according to an embodiment of the present invention. In the present embodiment, the signal receiving portion is a sensor, but the signal receiving portion is not limited thereto, and may be any device having a function of sensing an analysis signal.

Preferably, as shown in FIG. 3, the projection light determination unit A includes a sensor 1a located at the upper left corner, a sensor 1b located at the upper right corner, a sensor 1c located at the lower left corner, and a sensor 1d located at the lower right corner. Similarly, although not shown, the projection light determination unit B includes a sensor 2b located at the upper left corner, a sensor 2b located at the upper right corner, a sensor 2c located at the lower left corner, and a sensor 2d at the lower right corner; the projection light determination unit C includes the a sensor 3a in the upper left corner, a sensor 3b in the upper right corner, a sensor 3c in the lower left corner, and a sensor 3d in the lower right corner; and the projection light determining unit D includes a sensor 4a in the upper left corner, a sensor 4b in the upper right corner, and a lower left corner. The sensor 4c of the corner and the sensor 4d located at the lower right corner.

Here, preferably, in each of the projection light determination units, the shape with the four sensors as vertices is a rectangle. The

sensors

1a and 1b in the projection light determination unit A and the sensors 2a and 2b in the projection light determination unit B are collinear, and the

sensors

1c and 1d in the projection light determination unit A and the sensors 2c and 2d in the projection light determination unit B are common. The lines are parallel to the horizontal sides of the rectangular plane (the horizontal direction in the figure is horizontal). This arrangement relationship is also applicable to the projection light determination unit C and the projection light determination unit D. Further, the

sensors

1a and 1c in the projection light determination unit A and the sensors 3a and 3c in the projection light determination unit C are collinear, and the

sensors

1b and 1d in the projection light determination unit A and the sensor 3b in the projection light determination unit C are 3d is collinear and is parallel to the vertical sides of the rectangular plane (the vertical direction in the figure is vertical). This arrangement relationship is also applicable to the projection light determination unit B and the projection light determination unit D.

It is to be noted that, in the present embodiment, the arrangement of the sensors in the projection light determination unit is merely an example.

In the following description, the projection light determining unit A in the upper left corner first receives the projection light signal as an example for description.

Specifically, when the determining unit determines that the projection light signal received by the signal receiving unit is greater than the threshold, corresponding control information is generated to adjust the projected image.

Specifically, for the sensor 1a, the sensor 1b, the sensor 1c, and the sensor 1d of the projection light determination unit A, the following, but not limited to, the following types of projection optical signal reception may occur:

1) at least three of the sensor 1a, the sensor 1b, the sensor 1c, and the sensor 1d receive the projection light signal;

2) Only the sensor 1a and the sensor 1b receive the projection light signal;

3) Only the sensor 1a and the sensor 1c receive the projection light signal

4) only the sensor 1b and the sensor 1d receive the projected light signal;

5) Only the sensor 1c and the sensor 1d receive the projection light signal.

For case 1), when at least three of the sensor 1a, the sensor 1b, the sensor 1c, and the sensor 1d receive the projection light signal, and the projection light signal is greater than the threshold, the area of the projection image is transmitted to the projection unit on the projection light determination unit A. In the case of an excessively large amount of control information, the control unit controls the projection lens to move and/or reduce the projected image toward the sensor 1d (ie, the sensor closest to the geometric center of the rectangular plane);

For case 2), when only the sensor 1a and the sensor 1b receive the projection light signal, the control unit transmits control information for the case where the projection image is biased upward with respect to the projection light determination unit A, and the control unit controls the projection lens to project the image. Move down and/or zoom out;

For case 3), when only the sensor 1a and the sensor 1c receive the projection light signal, the control unit transmits control information for the case where the projection image is projected to the left for the projection light determination unit A, and the control unit controls the projection lens to project the image. Move to the right and/or zoom out;

For case 4), when only the sensor 1b and the sensor 1d receive the projection light signal, it indicates that, similar to the case 2), with respect to the projection light determination unit A, the projection image is biased upward, and the control unit controls the projection lens to project the projection image downward. Move and/or zoom out; and

For case 5), when only the sensor 1c and the sensor 1d receive the projection light signal, it indicates that, relative to the projection light determination unit A, similar to case 3), the projection image is biased to the left, and the control unit controls the projection lens to project the projection image Move right and/or zoom out. Please note that the reduction includes unilateral reduction and overall reduction.

By the above action (ie, when the other signal receiving portion receives the projected light signal in addition to the sensor 1d closest to the geometric center, the projected image is moved and/or scaled toward the sensor 1d closest to the geometric center until only the sensor 1d The projection light signal is received such that in the projection light determination unit A, only the sensor 1d receives the projection light signal.

Next, the projection light determination unit B is entered to perform processing. At this time, the projection light determination unit B may exhibit the following projection light signal reception condition 1) and the projection light signal reception condition similar to the projection light determination unit A:

1) The sensor 2a, the sensor 2b, the sensor 2c, and the sensor 2d do not receive the projection light signal.

Specifically, for case 1), when neither the sensor 2a, the sensor 2b, the sensor 2c, and the sensor 2d receives the projection light signal, the control unit controls the projection lens to move and/or amplify the projection image again until the sensor 2a, the sensor At least one of 2b, sensor 2c, and sensor 2d receives the projected light signal. Please note that the magnification also includes overall magnification and single-sided magnification.

For the case of the projection light signal reception similar to the projection light determination unit A, the control processing of the projection image is the same as that of the projection light determination unit A. For example, when at least three of the sensor 2a, the sensor 2b, the sensor 2c, and the sensor 2d receive the projection light signal, indicating that the projected image area is too large on the projection light determination unit B, the control unit will direct the projection image toward the sensor 2c (ie, The sensor closest to the geometric center of the rectangular plane moves and/or zooms out. Note that the movement and/or scaling of the projected image is such that the sensor 1d in the projected light determination unit A still receives the projected light signal as a standard.

By the above operation, in the projection light determination unit B, only the sensor 2c receives the projection light signal.

Similarly, similar processing is performed on the projection light decision units C and D, so that in the projection light determination unit C, only the sensor 3b receives the projection light signal, and in the projection light determination unit D, only the sensor 4a receives the projection light signal.

Finally, for the entire projection image adjusting device, only the sensor 1d receives the projection light signal in the projection light determination unit A, only the sensor 2c receives the projection light signal in the projection light determination unit B, and only the sensor 3b receives the projection light determination unit C. When the optical signal is projected and the sensor 4a receives the projected light signal in the projected light determining unit D, the entire projected image adjusting process is completed. At this time, a projected image that meets the user's expectations is obtained.

In addition, according to an embodiment of the present invention, a projection image adjustment method is also provided. 4 shows a flow chart of a projection image adjustment method in accordance with one embodiment of the present invention.

As in the embodiment of the projection image adjusting device according to the present invention described with reference to FIGS. 1 to 3, in the embodiment of the present projection image adjusting method, a rectangular projection screen will be described as an example. The projection light determination unit A in the upper left corner, the projection light determination unit B in the upper right corner, the projection light determination unit C in the lower left corner, and the projection light determination unit D in the lower right corner are respectively disposed at the four vertex angles of the rectangular screen.

After the projection system is activated, in step S101, first, the sensor (ie, the signal receiving portion) in the projection light determination unit receives ambient light as a threshold, and the projection lens will project an image.

In step S102, it is determined whether or not any one of the four projection light determination units A, B, C, and D has received the projection light signal. If none of the four projection light determination units A, B, C, and D receives the projection light signal, the process proceeds to step S103, and the projection image is moved/scaled until at least one of the four projection light determination units A, B, C, and D The person receives the projected light signal.

Similarly, the projection light determination unit A in the upper left corner first receives the projection light signal as an example for description.

When the projection light signal is greater than the threshold value, the sensor 1a, the sensor 1b, the sensor 1c, and the sensor 1d of the projection light determination unit A perform different projection image adjustment determinations according to different projection light signal receptions (step S104).

Specifically, the projection light signal receiving condition of the projection light determining unit A includes but is not limited to:

2) Only the sensor 1a and the sensor 1b receive the projection light signal;

3) Only the sensor 1a and the sensor 1c receive the projection light signal

4) only the sensor 1b and the sensor 1d receive the projected light signal;

5) Only the sensor 1c and the sensor 1d receive the projection light signal.

The determination of the specific projection image adjustment in different cases has been explained in the embodiment of the projection image adjusting device according to the present invention, and details are not described herein again.

In the projection light determination unit A, only the sensor 1d receives the projection light signal, and enters the projection light determination unit B to perform processing. The different projection light signal reception conditions of the sensors in the projection light determination units B, C, and D and the corresponding projection image adjustment judgments are not described herein again.

Finally, in step S105, it is judged whether or not the sensor closest to the geometric center in each of the image signal processing units receives the projection light signal, and if so, the projection image adjustment is completed, and if not, returns to step S104 to continue the projection image adjustment. That is, in the projection light determination unit A, only the sensor 1d receives the projection light signal, only the sensor 2c of the projection light determination unit B receives the projection light signal, and only the sensor 3b of the projection light determination unit C receives the projection light signal and the projection light determination unit When the sensor 4a in D receives the projection light signal, the entire projection image adjustment process is completed (S106). At this time, a projected image that meets the user's expectations is obtained.

It can be understood that the projection image adjusting device and method according to the present invention can also be applied to a designated projection area having an irregular polygon shape as long as the geometric center of gravity of the irregular polygon falls inside the shape. When the shape of the specified projection area is an irregular polygon, the geometric center is the geometric center of gravity.

FIG. 5 shows an arrangement example of a projection light determination unit according to another embodiment of the present invention, and FIG. 6 shows a detailed configuration of a broken line portion of FIG. 5. Hereinafter, a specific operation of the projection image adjusting device will be described by taking the irregular pentagon as an example with reference to FIGS. 5 and 6.

As shown in FIG. 5, projection light determining units A, B, C, D, and E are respectively disposed at five apex angles of the irregular pentagon. Preferably, after the projection system is activated, the projection light determination units A, B, C, D, E receive the ambient light and the projection light, and generate and transmit the control information based on the kind of the received light.

The difference from the above embodiment is that the projection light decision unit A includes the first signal receiving portion 1a' and the two second signal receiving portions 1b' and 1c' for receiving the ambient light and the projected light. Preferably, when the projection light determining unit is disposed at the vertex portion, the first signal receiving portion 1a' is disposed closer to the geometric center of gravity of the designated projection region than the two second signal receiving portions 1b' and 1c', And the two second signal receiving portions 1b' and 1c' are arranged on two straight lines a' and b': both of the straight lines pass through the first signal receiving portion 1a' and respectively with the projection regions forming the vertex portion The edges a and b are parallel. An advantage of this arrangement is that the position and size of the projected image can be more easily adjusted by scaling the projected image in accordance with the shape of the designated projection area. It will be appreciated that one of ordinary skill in the art can appropriately increase the number of signal receiving portions as needed.

Likewise, in the present embodiment, the ambient light signal is used as a threshold. The judging unit judges the relationship between the intensity of the light received by the first signal receiving unit 1a' and the two second signal receiving units 1b' and 1c' and the threshold value, thereby generating corresponding control information.

Specifically, when the determining unit determines that the projection light signal received by the signal receiving unit is greater than the threshold, corresponding control information is generated to adjust the projected image. For example, when the signal receiving unit other than the first signal receiving unit 1a′ receives the projection light signal and the projection light signal is greater than the threshold value, the control unit transmits a case where the projected image area is excessively large on the projection light determining unit A. Control information, the control unit controls the projection lens to move and/or reduce the projected image toward the first signal receiving portion 1a' until the first signal receiving portion 1a' closest to the geometric center of gravity of the irregular pentagon receives the projected light signal .

Next, the projection light determination unit B is entered to perform processing. At this time, if none of the signal receiving sections in the projection light determining unit B receives the projection light signal, the control unit controls the projection lens to again move and/or enlarge the projection image until the signal receiving section of the projection light determination unit B At least one of them receives the projected light signal. Otherwise, it is the same as the control processing for the projection light determination unit A, that is, moving the projection image toward the signal receiving portion closest to the geometric center of gravity of the irregular pentagon until only the geometric center of gravity of the irregular pentagon is closest The signal receiving unit receives the projected light signal. The reductions and enlargements used herein include overall reduction and enlargement as well as unilateral reduction and enlargement.

Similarly, similar processing is performed on the projection light decision units C, D, and E such that among the projection light determination units C, D, and E, only the signal receiving portion closest to the geometric center of gravity of the irregular pentagon receives the projection light signal. At this time, the entire projection image adjustment process in the case where the designated projection area is an irregular pentagon is completed.

In summary, with the projection image adjusting device and the projection image adjusting method according to the present invention, the lens adjustment and the image scaling can be automatically performed according to the received projection light signal of the projection light determining unit, and the projection image can be quickly adjusted. To the location that the user needs, without the need to specifically assign staff to deal with such problems, which greatly saves manpower and time costs.

Although the projection image adjusting device and the projection image adjusting method according to the present invention have been described above with reference to the accompanying drawings, the present invention is not limited thereto, and those skilled in the art should understand that, without departing from the scope of the appended claims Various changes, combinations, sub-combinations, and variations can be made in the subject matter or scope.

Claims

A projection image adjusting device, comprising:

a projection lens for projecting an image;

a plurality of projection light determining units, the plurality of projection light determining units being disposed at respective vertex portions of the designated projection area, and each of the plurality of projection light determining units for receiving ambient light and projection light, and based on Generating and transmitting control information for the type of received light;

a control unit that sequentially receives the control information transmitted by each of the projection light determination units and adjusts the projection lens based on the control information.
The projection image adjusting device according to claim 1, wherein each of the plurality of projection light determining units comprises:

a first signal receiving portion for receiving ambient light and projected light and at least two second signal receiving portions, wherein the first signal is received when the projection light determining unit is disposed at the vertex portion a portion disposed closer to a geometric center of the designated projection area than the at least two second signal receiving portions;

a determining unit, wherein the determining unit determines whether the ambient light or the projection light is received by each of the first signal receiving unit and the at least two second signal receiving units, when the intensity of the received light is greater than a threshold The determination is the projection light, and when the intensity of the received light is equal to or smaller than the threshold, it is determined that the ambient light is generated, and the corresponding control information is generated.
The projection image adjusting device according to claim 2, wherein

The at least two second signal receiving portions are disposed at least on two straight lines: the two straight lines pass through the first signal receiving portion and respectively form two of the projection regions forming the apex portion The sides are parallel.
The projection image adjusting device according to claim 2, wherein

When it is determined that, in one of the projection light determining units, the projection light determining unit receives the projection light by at least one of the second signal receiving units, the control unit controls the projection based on the control information a lens, thereby moving and/or reducing the projection image toward the first signal receiving portion of the projection light determining unit until only the first signal receiving portion receives the projection light.
The projection image adjusting device according to claim 2, wherein

The control unit controls the projection based on the control signal when it is determined that none of the first signal receiving portion and all of the second signal receiving portions in the projection light determining unit receive the projection light The lens moves and/or enlarges the projected image until the projected light determining unit receives the projected light signal.
The projection image adjusting device according to claim 5, wherein

In each of the projection light determining units, when only the first signal receiving portion closest to the geometric center receives the projected light signal, the projected image adjusting device completes the adjustment of the projected image.
The projection image adjusting device according to any one of claims 2 to 6, wherein

The shape of the specified projection area is a regular polygon or an irregular polygon, wherein when the shape of the specified projection area is the irregular polygon, the geometric center is a geometric center of gravity, and the geometric center of gravity is located at the Inside the regular polygon.
A projection image adjustment method, comprising the steps of:

Setting a plurality of projection light determining units at respective vertex portions of the designated projection area, and projecting an image with the projection lens;

Each of the plurality of projection light determination units receives ambient light and projection light, and generates and transmits control information based on the kind of the received light;

The control unit transmits the control information transmitted by each of the projection light determination units in sequence and adjusts the projection lens based on the control information.
The projection image adjustment method according to claim 8, wherein each of the plurality of projection light determination units comprises:

a first signal receiving portion for receiving ambient light and projected light and at least two second signal receiving portions, wherein the first signal is received when the projection light determining unit is disposed at the vertex portion a portion disposed closer to a geometric center of the designated projection area than the at least two second signal receiving portions;

a determining unit, wherein the determining unit determines whether the ambient light or the projection light is received by each of the first signal receiving unit and the at least two second signal receiving units, when the intensity of the received light is greater than a threshold The determination is the projection light, and when the intensity of the received light is equal to or smaller than the threshold, it is determined that the ambient light is generated, and the corresponding control information is generated.
The projection image adjusting method according to claim 9, wherein

The at least two second signal receiving portions are disposed at least on two straight lines: the two straight lines pass through the first signal receiving portion and respectively form two of the projection regions forming the apex portion The sides are parallel.
The projection image adjusting method according to claim 9, wherein

When it is determined that, in one of the projection light determining units, the projection light determining unit receives the projection light by at least one of the second signal receiving units, the control unit controls the projection based on the control information a lens, thereby moving and/or reducing the projection image toward the first signal receiving portion of the projection light determining unit until only the first signal receiving portion receives the projection light.
The projection image adjusting method according to claim 9, wherein

The control unit controls the projection based on the control signal when it is determined that none of the first signal receiving portion and all of the second signal receiving portions in the projection light determining unit receive the projection light The lens moves and/or enlarges the projected image until the projected light determining unit receives the projected light signal.