JP2003234983A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately display a pointer at a position indicated by a user in spite of a distortion, etc., generated to projected images in a projector for projecting images. <P>SOLUTION: Reference lines 12p for defining a coordinate of an image area projected therein are projected on a screen 200 superimposed on the images to be projected. A projection point 302 indicated by the user using a laser pointer 300 is taken photo images by a CCD camera 140 with the reference lines 12p. From the photo images, a coordinate value S(x, y) of the projection point 302 is calculated, a coordinate value GP(x, y) of a guide mark 192 is then controlled to approach the coordinate value S(x, y), and the pointer is displayed at the position of the coordinate value GP(x, y) when the distance between the both becomes within a threshold value. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projector for projecting an image on a screen, and more particularly to a projector for synthesizing and projecting a pointer suitable for presentation.

[0002]

2. Description of the Related Art Generally, projectors are used for presentations to a large number of people because they enlarge and project images such as characters and graphs on a screen.
At the time of this presentation, it is a widely practiced practice to point the image projected on the screen by using a laser pointer or the like to make the presenter (user) easily understand the explanation. However, direct pointing of the projected image with the laser pointer is difficult to see due to camera shake, and because it is monochromatic, there is no sharpness. Therefore, in recent years, JP-A-11-27167
As described in Japanese Patent Publication No. 5, a CCD (Charge Coupled Device) camera built in the projector detects a point illuminated by a laser pointer by a user, and the pointer (marking) is placed at the same point as the illuminated point.
A technique of displaying an image has been developed.

By the way, the projector is not always arranged on an axis orthogonal to the screen because of its mobility. For example, depending on the place of use, there is a case where the image has to be projected obliquely to the screen, and there is a case where the image is hung from the ceiling even if the projector is fixedly used. If the projector is used in such an arrangement, the projected image will be distorted. Even if the projected image is distorted in this way, if the degree is small, it may be used by allowing it, but in recent years, by generating an image predistorted in the direction opposite to the distortion direction,
A correction technique has also been proposed in which the projected image results in a correct rectangle.

[0004]

However, in the technique described in the above publication, the projected image is distorted because the irradiation point of the laser pointer is calculated on the assumption that the projected image is correctly rectangular. However, if the above assumption is broken as in the case where the correction technique is applied, the accuracy of the position where the pointer is displayed with respect to the irradiation point is naturally lowered. The present invention is
It was made in view of such circumstances, and the purpose is to be able to accurately display the pointer at the point pointed to by the user even if the projected image is distorted. To provide a new projector.

[0005]

To achieve the above object, a projector according to the present invention is a projector for projecting an image on a screen, and a reference point serving as a reference for defining coordinates of the image area. A reference point projecting means for synthesizing the image with the image and projecting it on the screen, a reference point projected by the reference point projecting means, and a light pointed by a user to the image area projected on the screen. Imaging means for imaging the irradiation point of the beam, calculation means for calculating the coordinate value of the irradiation point in the projected image area from the image taken by the imaging means, and the calculated coordinate value for the image to be projected. And a synthesizing means for synthesizing the pointer at a corresponding position. According to the present invention, while the image to be actually projected includes the reference point, the projected reference point and the irradiation point of the pointed light beam are imaged, and the coordinate value of the irradiation point is calculated from the positional relationship. , Since the pointer is combined and projected at the position corresponding to the coordinate value, even if the projected image is distorted, the calculated coordinates are calculated in consideration of the distortion, and as a result, the position accuracy of the combined pointer is improved. It is possible to raise it.

In the present invention, the synthesizing means synthesizes a guide mark as a substitute for the pointer before synthesizing the pointer, and the imaging means images the guide mark together with the reference point and the irradiation point, and the calculating means. Calculates the coordinate value of the guide mark together with the coordinate value of the irradiation point, and the synthesizing means moves the guide mark in a direction in which the difference between the calculated coordinate value of the irradiation point and the coordinate value of the guide mark becomes smaller. At the same time, it is preferable that the pointers are combined when the difference is within a preset threshold value. According to this configuration, even if the coordinate value of the irradiation point and the coordinate value of the guide mark differ, the pointer is combined after being corrected so as to be within the threshold value, so that the position accuracy of the pointer is further improved. It becomes possible.

In the present invention, the light beam is pointed in a shape selected by the user from among a plurality of shapes, and a shape specifying means for specifying the shape of the pointed light beam from the image picked up by the image pickup means. It is preferable that the light emitting device further comprises means, and the synthesizing means changes the shape of the pointer to be synthesized for each shape of the specified light beams. According to this configuration, the shape of the pointer to be combined can be changed according to the shape of the pointed light beam, so that it is possible to further enhance the presentation effect.

In the present invention, the light beam is pointed in a shape selected by the user from among a plurality of shapes, and a shape specifying means for specifying the shape of the pointed light beam from the image taken by the image pickup means is specified. It is preferable that the apparatus further comprises means, and the synthesizing means synthesizes or erases the pointer according to the specified shape of the light beam. According to this configuration, the pointer can be erased according to the shape of the pointed light beam when it is unnecessary in the presentation.

In the present invention, the reference point and the guide mark do not need to be visually recognized by the user or the like. Therefore, it is desirable that the reference point projecting unit projects the reference point and the guide mark with invisible light, for example, infrared light.

In the present invention, when the projection image control means for controlling the image to be projected on the screen from the image picked up by the image pickup means is provided, for example, the function of controlling the brightness of the projection image and the distortion of the projection image are controlled. It is possible to realize a function of correcting and a function of automatically adjusting the focus of the projected image. In each case, since the image pickup means for picking up the projected reference point and the irradiation point of the light beam is used for various functions, no separate image pickup means is required, and as a result, complication of the configuration can be avoided.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

<Overall Configuration> FIG. 1 is a plan view showing an optical configuration of the projector according to the embodiment. As shown in this figure, a white light source 102 that emits white light, such as a halogen lamp, is provided inside the projector 100. The white light emitted from the white light source 102 has three mirrors 106 and 2 arranged inside.
R (red), G by the dichroic mirror 108
(Green) and B (blue) are separated into three primary colors. Of these, R color light is guided to an LCD (Liquid Crystal Display) panel 10-R, and similarly, each of G color light and B color light is It is led to the LCD panels 10-G and 10-B, respectively.

Here, the LCD panel 10-R functions as a light modulator for generating an R primary color image, and similarly, the LC panel 10-R
Each of the D panels 10-G and 10-B has a G
And B as a light modulator for generating primary color images. The B-color light has a longer optical path than the other R-color light and the G-color light.
Is guided through a relay lens system 130 composed of

LCD panels 10-R, 10-G and 1
The lights respectively modulated by 0-B, that is, the respective primary color images are incident on the dichroic prism 112 from three directions. Then, in the dichroic prism 112, the R and B color lights are refracted by 90 degrees, while the G color light goes straight, so that the primary color images are combined to form a color image. This color image is incident on the dichroic prism 118.

In addition to the ordinary white light source 102, the projector 100 is provided with an infrared light source 116 which emits infrared light, and the infrared light is guided to the LCD panel 10-IR. The LCD panel 10-IR is the LCD panel 10-
It has the same resolution and size as R, 10-G, and 10-B, and actually generates an image including a reference line and guide marks.

The infrared light modulated by the LCD panel 10-IR enters the dichroic prism 118 and is refracted by 90 degrees, while the light emitted from the dichroic prism 112 goes straight through the dichroic prism 118. Therefore, in the projector 100, the infrared image indicating the reference line and the guide mark is combined with the color image obtained by combining the primary color images, and the combined image is formed by the lens group 12.
0 causes it to be projected onto the screen 200.

Here, the reference line means the LCD panel 10-.
In the IR, an image is generated with only the pixels located at the outermost periphery among the pixels arranged in a matrix in the ON state (transmission state). Therefore, as shown in FIG. 4, the reference line 12p projected by the infrared ray on the screen always coincides with the contour line 10p of the color image.
Further, the guide mark is a mark for position control used when the projector 100 synthesizes the pointer, as indicated by reference numeral 192 in FIG. 4, and as will be described later in detail, the user can use the laser pointer 300. The pointer indicating the position pointed in the screen projection image when the irradiation point 302 pointed by is controlled so as to approach and the distance between them is within the error range (within a preset threshold value). Switch to.

In this embodiment, the shape of the light beam of the laser pointer 300 is, for example, as shown in FIG.
One of the three types shown in (b) and (c) is selected by the user and emitted. Of these, Figure 8
The shape shown in (a) indicates to display a pointer 194 having a pattern as shown in FIG. 9 (a), for example. Similarly, the shape shown in FIG. 8B indicates to display the pointer 194 having a pattern as shown in FIG. 9B, for example. However, the shape as shown in FIG. 8C indicates to erase the displayed pointer 194.

On the other hand, the projector 100 is provided with a CCD camera 140, and images the image projected on the screen 200 including the reference line together with the irradiation point 302 pointed by the user with the laser pointer 300. In addition, the CCD camera 140 has a screen 20
The image projected on 0 is not captured over the entire wavelength range, but is captured through a filter that transmits only the laser wavelength of the laser pointer 300 and the wavelength of infrared light from the infrared light source 116.

Next, the electrical configuration of the projector 100 will be described with reference to FIG. In FIG. 2, the image analysis unit 152 analyzes the image taken by the CCD camera 140. The beam shape identifying unit 154 first irradiates the laser pointer 300 from the captured image analyzed by the image analyzing unit 152, and the screen 200
It is determined whether the irradiation point 302 is formed on the
When it is determined that the irradiation point 302 is formed on the screen 200, the shape of the irradiation point 302 is further specified.

On the other hand, the coordinate calculation unit 156 includes the image analysis unit 1
From the captured image analyzed by 52, the screen 200
Coordinate S (x, y) of the irradiation point with respect to the image projected on
And the guide mark (pointer) coordinate value GP (x,
y) is calculated respectively. Here, the coordinate calculation unit 156
Is the coordinate value GP (x, y) so that the coordinate value on the image is correct even when the projected image is distorted.
And the coordinate value S (x, y) is obtained as follows, for example. That is, as shown in FIG. 5, the coordinate calculation unit 156 firstly calculates the reference line 1 projected on the screen 200.
2p is specified, secondly, the opposite sides of the quadrangle defined by the reference line 12p are divided at equal proportions to virtually create the mesh 14p, and thirdly, the mesh 14p is defined. Irradiation point 302
Let S (x, y) be the coordinate value of the intersection closest to
Of the intersections defined by the mesh 14p, the coordinate value of the intersection closest to the projected guide mark 192 is GP.
Let (x, y).

Here, in FIG. 5, as the mesh 14p,
An example in which the quadrangle defined by the reference line 12p is divided into 8 × 8 is shown, but this example is merely for convenience of description, and in actuality, it is divided into finer parts. This is because the accuracy of the coordinate value improves as the number of divisions increases. As will be described later with reference to the flowchart, the guide mark is controlled so as to approach the irradiation point. However, when the user irradiates the beam using the laser pointer 300 for the first time immediately after the power is turned on, the guide mark is not displayed. In some cases, the coordinate calculation unit 156 outputs the coordinate value of a predetermined fixed point (for example, apex P1) as the coordinate value GP (x, y) in this case. .

If the projected image is correctly displayed in a rectangle, the coordinate calculation unit 156 will determine the coordinate value GP.
(X, y) and the coordinate value S (x, y) may be simply calculated as follows. That is, the coordinate calculation unit 156 first identifies the reference line 12p projected on the screen 200, and secondly, as shown in FIG.
Apex P of a quadrangle defined by the reference line 12p
Of 1, P2, P3, and P4, the coordinate value S (x, y) is calculated using three points that are close to the irradiation point 302 as reference points. The value GP (x, y) may be calculated. For example, when the projection image is displayed in a rectangle as shown in FIG. 4 and the irradiation point 302 is located in the projection image, the coordinate calculation unit 156 uses the vertices P1, P2, and P3 as reference points, The coordinates of the x component (horizontal component) and the y component (vertical component) are calculated.

Next, the position controller 158 determines the coordinate value GP.
The coordinate value information corrected so that (x, y) becomes the coordinate value S (x, y) is output. Since the position of the guide mark 192 obtained at this time is indicated by the coordinate value GP (x, y), the position control unit 158 determines that the coordinate value GP (x, y).
y) as a starting point, coordinate values S (x, y) of the irradiation point 302
The coordinate value of the point moved by a fixed distance (for example, half the distance of the coordinate value GP (x, y) and the coordinate value S (x, y)) in the direction is output as coordinate value information.

On the other hand, the G / P switching instructing section 160 determines whether or not the distance between the coordinate value GP (x, y) and the coordinate value S (x, y) calculated by the coordinate calculating section 156 is within the threshold value. If the determination result is affirmative, pointer display is instructed, and if the determination result is negative, guide mark display is instructed. The selector 162 supplies the coordinate value information output by the position control unit 158 to the Gm image generation unit 164, which will be described below, when the G / P switching instruction unit 160 instructs pointer display, while P
If the switching instruction unit 160 has instructed to display the guide mark, it is supplied to the P image image generation unit 174 described later.

The Gm image generation section 164 has a selector 162.
When the coordinate value information is supplied by the position control unit 158, an image signal indicating an image in which, for example, a “+”-shaped guide mark is arranged at the point indicated by the coordinate value information is generated, while the selector is selected. If no coordinate value is supplied by the position control unit 158 by 162, no image signal is generated. On the other hand, the reference line generation unit 166
An image signal indicating a rectangular image matching the periphery of the effective image area is generated.

The superimposing section 168 superimposes the image signal generated by the reference line generating section 166 on the image signal generated by the Gm image generating section 164 and outputs it. The image signal superimposed by the superimposing unit 168 is supplied to the drive circuit 180-IR that drives the LCD panel 10-IR, whereby the image including the guide mark and the reference line is displayed on the LCD panel 10-IR. It is actually generated.

The pointer storage unit 172 stores a plurality of display patterns to be pointers in advance, and reads out a pattern corresponding to the shape of the irradiation point 302 specified by the beam shape specifying unit 154. The P image generation unit 174
An image signal indicating an image in which the pointer of the pattern read from the pointer storage unit 172 is arranged at a point corresponding to the coordinate value supplied from the position control unit 158 via the selector 162 is generated. However, the beam shape identifying unit 154
When the shape of the irradiation point 302 is specified to be a shape instructing to erase the pointer (see FIG. 8C),
Alternatively, if the coordinate value information of the position control unit 158 is not supplied by the selector 162, the P image generation unit 174
Does not generate any image signal. On the other hand, the projection image input unit 176 inputs an image signal DVin indicating an image to be enlarged and projected by the projector 100.

The superimposing section 178 superimposes the image signal DVin input to the projection image input section 176 on the image signal generated by the P image generating section 174 and outputs it. The image signal superimposed by the superimposing unit 178 is separated into image signals indicating the RGB primary color components, and then the R image signal is supplied to the drive circuit 180-R which drives the LCD panel 10-R. , G image signals drive circuit 180- for driving LCD panel 10-G.
The image signal of B supplied to G is displayed on the LCD panel 10-B.
Is supplied to the drive circuit 180-B that drives the. This allows LCD panels 10-R, 10-G and 10-B.
Then, if the P image generation unit 174 has generated an image signal indicating an image in which the pointer is arranged in the color image indicated by the image signal DVin, the image in which the pointer is combined is actually generated. . The LCD panel 10
As described above, the color image combined by -R, 10-G and 10-B is further combined with the infrared image generated by the LCD panel 10-IR and projected on the screen 200. .

<Pointer Display Operation> Next, details of the pointer display operation in the projector 100 will be described. FIG. 3 is a flowchart showing the processing operation of the projector. First, the image DVin input by the projection image input unit 176 is separated into RGB primary color components, and the drive circuits 180-R, 180-G and 180-B are separated.
And the image generated by the reference line generation unit 166 are supplied to the drive circuit 180-IR (step S11). As a result, the input image DVi
n is a reference line 12p that matches the contour line 10p of the image.
Are superposed by infrared rays and enlarged and projected on the screen 200. On the other hand, the enlarged and projected image is captured by the CCD camera 140, and the captured image is
It is analyzed by the image analysis unit 152.

Next, the beam shape specifying unit 154 determines whether the image projected by the user is irradiating the image projected on the screen 200 with the beam by using the laser pointer 300. It discriminates from (step S12). If the determination result is negative, the projector 100 does not need to perform any processing regarding the display of the pointer, and thus enters the standby state. When the determination result is affirmative, the beam shape identifying unit 154 identifies the shape of the irradiation point 302 irradiated on the screen 200 by the beam (step S1).
3) It is determined whether or not the specified shape is the shape (■) that instructs the deletion of the pointer (step S14).

Here, if the beam shape specifying unit 154 determines that the shape of the irradiation point 302 is a shape for instructing the deletion of the pointer, the P image generating unit 174 does not generate an image in which the pointer is arranged. If the pointer is displayed up to, it is eventually erased (step S15).
On the contrary, when the beam shape identifying unit 154 determines that the shape of the irradiation point 302 is not the shape that instructs the pointer to be erased, the shape of the irradiation point 302 is further changed to the shape A shown in FIG. It is determined whether or not there is (step S1
6).

If the result of this determination is affirmative, the pointer pattern (see FIG. 9A) corresponding to the shape A is read from the pointer storage unit 172 (step S1).
7) On the other hand, when the determination result is negative, the pointer pattern (see FIG. 9B) corresponding to the shape B is read from the pointer storage unit 172 (step S1).
8).

On the other hand, the coordinate calculation unit 156 has the image analysis unit 1
From the result of the image analysis by 52, the guide mark 192
(Or pointer 194) coordinate value GP (x, y),
The coordinate value S (x, y) of the irradiation point 302 is obtained as described above (step S19). As a result, the position control unit 158 uses the coordinate value GP (x, y) as a starting point to move the irradiation point 302 in the coordinate value S (x, y) direction at a constant distance (for example, the coordinate value GP (x, y)). And the coordinate value information indicating the coordinate value shifted by half the distance of the coordinate value S (x, y)) is output (step S20).

On the other hand, when both coordinate values are obtained, the G / P switching instructing section 160 determines whether the distance between the coordinates indicated by both coordinate values is within the error range (within a preset threshold value). It is determined whether or not (step S21). When the result of this determination is negative, the selector 162 supplies the coordinate value information from the position controller 158 to the Gm image generator 164 (step S22). Accordingly, the Gm image generation unit 164
Generates an image in which a "+"-shaped guide mark is arranged at the point indicated by the coordinate value information.

Therefore, for example, as shown in FIG. 6, the guide mark is located at the point G, until just before,
Moreover, if the irradiation point 302 has not moved, the guide mark 192 will move in the direction of the irradiation point 302 from that point and by a half distance. Further, when the irradiation point 302 is moved by the user, the guide mark 192 moves from the original display point to the irradiation point 302 at the present time (after the movement) and by a half distance (not shown). In any case, by repeating the processing from steps S19 to S22, the guide mark 1
92 gradually approaches the irradiation point 302.

Then, the guide mark 192 indicates the irradiation point 30.
Gradually approaching 2, the distance is within the error range,
If the determination result of step S21 is affirmative, the selector 162 supplies the coordinate value information by the position control unit 158 to the P image generation unit 174 (step S23). As a result, the P image generation unit 174 generates an image signal in which the pointer of the pattern read in step S17 or S18 is arranged at the point indicated by the coordinate value information.

Therefore, for example, the irradiation point 302 is shown in FIG.
When the pointer of the pattern shown in FIG. 9A is read because of the shape shown in FIG. 9A, the position within the error range close to the irradiation point 302 is shown in FIG. The pointer 194 is displayed by switching from the guide mark 192.

When the irradiation point 302 moves from the state where the pointer 194 is displayed and the distance exceeds the error range, the determination result of step S21 becomes negative, so that the pointer 194 is replaced. The guide mark 192 is displayed again on the screen, and the control for approaching the irradiation point 302 is executed. Also, the shape A of the irradiation point 302
When the shape of the irradiation point 302 changes to the other while the pointer 194 corresponding to one of the shape B (see FIG. 8A) and the shape B (see FIG. 8B) is displayed, the determination in step S16 Since the pattern read by is also changed, the pointer 194 is also changed to the pattern corresponding to the other shape. Further, the irradiation point 302 is shown in FIG.
When the shape changes to, the pointer 194 is erased in step S14. Even after the pointer 194 is erased, the irradiation point 302 has the shape shown in FIG. 8A or FIG. 8B, and the distance between the irradiation point 302 and the guide mark 192 is within the error range. Then, the pointer 194 having a pattern corresponding to the irradiation point 302 is displayed.

As described above, according to this embodiment, the laser pointer 3 is moved from the reference line 12p that matches the contour of the image.
00 is used to detect the coordinates of the irradiation point 302, the position of the guide mark 192 is repeatedly corrected so as to approach the coordinates, and the distance between the irradiation point 302 and the guide mark 192 falls within the error range. When it becomes, the display is switched from the guide mark 192 to the pointer 194. Therefore, even if the image projected on the screen is distorted, the pointer 194 is moved close to the pointed position with respect to the distorted image. It becomes possible to display. Further, it is possible to instruct to change the pointer to be displayed and to erase the displayed pointer according to the shape of the irradiation point 302.
It is possible to realize a presentation that reflects the user's will in detail. In addition, since the reference line 12p and the guide mark 192 are displayed by infrared rays of invisible light, the reference line 12p and the guide mark 192 are not visually recognized including the user, and therefore, the presentation effect of the presentation is not hindered.

In the present invention, the shape of the irradiation point 302 may be other than the shape shown in FIG. 8 as long as the image analysis section 140 for analyzing the image taken by the CCD camera 140 can be distinguished. . Similarly, the pointer 194 corresponding to the shape of the irradiation point 302 is not limited to that shown in FIG.
It may be a moving object such as an animation pointer. Further, in the embodiment, the reference line 12p is displayed so as to match the contour of the image projected on the screen 200. In short, even if the projected image is distorted, the coordinates of the image are correctly detected. It should be a standard for Therefore, for example, only the vertices of the projected image may be used,
The mesh 14p in FIG. 5 may be actually displayed instead of being virtual.

In addition, in the embodiment, the irradiation point 3
Instructed to change or delete the pointer to be displayed according to the shape of 02. For example, a personal computer (PC)
If the display image is to be projected, a click operation for the projected image may be instructed like a mouse. Therefore, in such a configuration, the irradiation point 3
If the trajectory of the pointer 194 traced by 02 is recognized on the PC side, so-called handwritten character input can be realized. Further, in the embodiment, the LCD panel 1
Although an image is formed using 0-R, 10-G, 10-B and 10-IR, and the image is projected, a so-called mirror device may be used to form an image.

Further, in the embodiment, the CCD camera 1
The captured image by 40 was used only for the presence / absence of the irradiation point 302, the shape, the coordinate value calculation, and the coordinate value calculation of the guide mark. good. For example, CCD camera 1
By detecting the brightness of the image projected on the screen, the distortion of the projected image, the focus, and the like by 40, and controlling the image to be projected according to the detection result, the image pickup means other than the CCD camera 140 is detected. It is possible to increase the added value of the projector without separately needing it.

[0044]

As described above, according to the present invention, in a projector for projecting an image, a pointer is accurately displayed at a position pointed to by a user even if the projected image is distorted. It becomes possible.

[Brief description of drawings]

FIG. 1 is a plan view showing an optical configuration of a projector according to an embodiment of the invention.

FIG. 2 is a block diagram showing an electrical configuration of the projector.

FIG. 3 is a flowchart showing a pointer display operation in the projector.

FIG. 4 is a diagram for explaining a usage state and the like of the projector.

FIG. 5 is a diagram showing an example of a screen projected by the projector.

FIG. 6 is a diagram showing an example of a screen projected by the projector.

FIG. 7 is a diagram showing an example of a screen projected by the projector.

FIG. 8 is a diagram showing an example of a shape of a light beam pointed by a user.

FIG. 9 is a diagram showing an example of pointers combined in the projector.

[Explanation of symbols]

10-R, 10-G, 10-B, 10-IR ... LCD panel 12p ... Reference line 100 ... Projector 116 ... Infrared light source 140 ... CCD camera 152 ... Image analysis unit 154 ... Beam shape identification unit 156 ... Coordinate calculation unit 164 ... Gm image generation unit 174 ... P image generation unit

Claims (7)

[Claims] 1. A projector for projecting an image on a screen, and a reference point projecting means for synthesizing a reference point, which is a reference for defining coordinates of the image area, with the image and projecting the image on the screen. A reference point projected by the reference point projection means, and an image pickup means for picking up an irradiation point of a light beam pointed by a user with respect to an image area projected on the screen, from a picked-up image by the image pickup means, It is characterized by comprising: calculation means for calculating the coordinate value of the irradiation point in the projected image area; and synthesizing means for synthesizing the pointer at the position corresponding to the calculated coordinate value with respect to the image to be projected. projector. 2. The synthesizing means synthesizes a guide mark in place of the pointer before synthesizing the pointer, the imaging means images the guide mark together with the reference point and the irradiation point, and the calculating means: The coordinate value of the guide mark is also calculated together with the coordinate value of the irradiation point, and the synthesizing means moves the guide mark in a direction in which the difference between the coordinate value of the calculated irradiation point and the coordinate value of the guide mark decreases. The projector according to claim 1, wherein a pointer is combined when the difference is within a preset threshold value. 3. The light beam is pointed in a shape selected by a user from among a plurality of shapes, and shape specifying means for specifying the shape of the pointed light beam from the image taken by the image pickup means. The projector according to claim 1, further comprising: the synthesizing unit varies a shape of a pointer to be synthesized for each shape of the identified light beams. 4. The light beam is pointed in a shape selected by a user from among a plurality of shapes, and shape specifying means for specifying the shape of the pointed light beam from the image taken by the imaging means is used. Further provided, the combining means, according to the shape of the identified light beam,
The projector according to claim 1, wherein the pointer is combined or erased. 5. The projector according to claim 1, wherein the reference point projection means projects the reference point with invisible light. 6. The projector according to claim 1, wherein the reference point projection means projects the guide mark with invisible light. 7. The projector according to claim 1, further comprising projection image control means for controlling an image to be projected on a screen from an image taken by the imaging means.