JP2006251182A - Image forming apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a clear image without causing a sense of incongruity for an observer. <P>SOLUTION: A first image forming part forms a partial image 51-1 on a screen or the like by initially (for example at the time t1) performing the scanning from the right to the left in a first direction, and thereafter (for example at the time t2) repeats the process for forming the partial image 51-1 on the screen or the like by performing the scanning from the left to the right in a second direction. A second image forming part forms a partial image 51-2 on the screen or the like by initially performing the scanning in the outward path in the second direction, and thereafter repeats the process for forming the partial image 51-2 by performing the scanning in the return path in the first direction. Accordingly, a gray monochromatic like image is sequentially projected on the screen or the like at each 60 [Hz], as a blending area 61. Thus, flicker due to tiling is hardly generated. The present invention can be applied to a projector. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus and method, and more particularly, to an image forming apparatus and method capable of forming a clear image that does not feel uncomfortable for an observer.

  Conventionally, image forming apparatuses such as projectors and printers are known. For example, a conventional image forming apparatus (see, for example, Patent Document 1) scans a light beam corresponding to a one-dimensional image (hereinafter referred to as a one-dimensional image light beam) in a predetermined scanning direction and projects it onto a screen or the like. As a result, a two-dimensional image is formed on the screen or the like.

  Further, the present applicant has filed an application (for example, Japanese Patent Application No. 2004-128374) regarding the following image forming apparatus (image display apparatus). In other words, the image forming apparatus already filed by the applicant of the present application first scans a one-dimensional image light beam with the first direction as a scanning direction and projects it onto a screen or the like, and then reverses the first direction. An image forming apparatus that repeatedly executes a process of scanning a one-dimensional image light beam in a second direction and projecting the same onto a screen or the like.

  Hereinafter, the first direction is referred to as the forward direction, and the second direction is referred to as the return direction. The image forming apparatus already filed as Japanese Patent Application No. 2004-128374 by the present applicant is particularly referred to as a reciprocating scanning image forming apparatus in order to distinguish it from other conventional image forming apparatuses. That is, the reciprocating scanning image forming apparatus refers to an image forming apparatus that can scan a one-dimensional image light beam in both the forward direction and the backward direction.

  A plurality of such reciprocating scanning image forming apparatuses are prepared, and each of the reciprocating scanning image forming apparatuses has a screen or the like so that a part of the reciprocating scanning image forming apparatus and a part of another adjacent image overlap each other. There is a demand for the realization of each method. That is, if an image formed on a screen or the like by each of a plurality of reciprocating scanning image forming apparatuses is hereinafter referred to as a partial image, when this technique is realized, the result is a 1 composed of a plurality of partial images. An entire image (hereinafter referred to as an entire image) is formed on a screen or the like.

Hereinafter, such a method is referred to as a tiling method. Hereinafter, a portion where two partial images are overlapped by a tiling method, that is, the above-described part of each of the two partial images is referred to as a blending region. That is, the blending area is a so-called marginal part.
US Pat. No. 5,982,553

  However, when the conventional reciprocating scanning image forming apparatus is simply used as it is and the tiling method is realized, the following first and second problems occur.

  That is, all of the plurality of conventional reciprocating scanning image forming apparatuses respectively form their own partial images on the screen or the like in the same output state, thereby realizing the tiling technique. In this case, the observer who observes the entire image composed of a plurality of partial images formed on the screen or the like in this way has a problem that the blending area of the entire image is visually recognized as flicker. This is the first problem.

  Further, when attention is paid to one partial image of such whole images, the partial image is formed on the screen or the like in both the forward direction and the backward direction as described above. In this case, for example, a plurality of partial images (a plurality of still images, here, for example, a plurality of frames) are sequentially formed on a screen or the like at predetermined time intervals. Assume that a moving image in which an object (image) moves quickly in the forward direction is formed on a screen or the like. In this case, two objects (first first) existing at different positions near the start point of scanning (a point where the scanning direction changes from the backward direction to the forward direction), that is, near the left side or the right side of a predetermined frame. If the object in the frame and the object in the next second frame are in an overlapping state (hereinafter referred to as a double image state), the second problem is that it is visually recognized by the observer. It is a problem.

  There is also a conventional method in which two or more conventional reciprocating scanning image forming apparatuses form the same partial images in the same region such as a screen and stack (stack) them. Hereinafter, such a method is referred to as a stacking method. Even if such a conventional stacking method is used in combination, the second problem occurs similarly. The second problem also occurs when one conventional reciprocating scanning image forming apparatus forms a single image on a screen or the like instead of a partial image constituting the entire image.

  The first problem and the second problem described above are that at least a part of an image formed on a screen or the like by a conventional reciprocating scanning image forming apparatus is uncomfortable or unclear to an observer. This results in the problem of being reflected in

  The present invention has been made in view of such a situation, and makes it possible to form a clear image that does not feel uncomfortable for an observer.

  The first image forming apparatus of the present invention superimposes a predetermined part of the first partial image and a predetermined part of the second partial image, so that the first partial image and the second partial image are An image forming apparatus for forming an image consisting of a plurality of block images constituting the first partial image in a first direction by first scanning with light corresponding to each of the plurality of block images constituting the first partial image. By irradiating each image formation target, the first partial image is formed on the image formation target, and then scanned in the second direction opposite to the first direction to be the image formation target. By irradiating each, the first image forming unit that repeatedly executes the process of forming the first partial image on the image forming target, and the second part substantially in synchronization with the first image forming unit Light corresponding to each of a plurality of block images constituting the image First, the second partial image is formed on the image forming target by scanning in the second direction and irradiating the image forming target, respectively, and then scanning in the first direction to scan the target. And a second image forming unit that repeatedly executes a process of forming a second partial image on the image forming target by irradiating each of the image forming targets.

  The light corresponding to each of the plurality of block images constituting the first partial image is first scanned in the second direction and irradiated to each image forming target in synchronization with the first image forming unit. As a result, the first partial image is formed on the image formation target, and then the first partial image is scanned by irradiating each of the image formation targets by scanning in the first direction. A third image forming unit that repeatedly executes a process to be formed on the image forming target, and light corresponding to each of the plurality of block images constituting the second partial image in substantially synchronization with the first image forming unit. First, the second partial image is formed on the image formation target by scanning in the first direction and irradiating each of the image formation targets, and then scanning in the second direction. By irradiating each image formation target, It can be a partial image to be provided further a fourth image forming unit to repeatedly execute a process of forming the image forming object.

  The first image forming method of the present invention is an image forming method corresponding to the above-described second image forming apparatus of the present invention, and the light corresponding to each of a plurality of block images constituting the first partial image. First, the first partial image is formed on the image formation target by scanning in the first direction and irradiating the image formation target, respectively, and then the direction opposite to the first direction A first image forming step of repeatedly executing a process of forming the first partial image on the image forming target by scanning in the second direction and irradiating the image forming target, respectively, The light corresponding to each of the plurality of block images constituting the second partial image is first scanned in the second direction and is irradiated to each image forming target substantially in synchronization with the processing of the image forming step. By doing so, the second partial image is drawn The second process of repeatedly forming the second partial image on the image formation target is performed by forming the image on the formation target, and then scanning in the first direction and irradiating the image formation target respectively. And an image forming step.

  Almost in synchronization with the processing of the first image forming step, the light corresponding to each of the plurality of block images constituting the first partial image is first scanned in the second direction to be an image formation target. By irradiating each, the first partial image is formed on the image forming target, and then the first partial image is scanned by scanning in the first direction and irradiating each image forming target. The third image forming step for repeatedly executing the processing for forming the image on the image forming target and the plurality of block images constituting the second partial image substantially in synchronization with the processing of the first image forming step. First, the corresponding partial light is scanned in the first direction and irradiated to the image formation target, thereby forming the second partial image on the image formation target, and then in the second direction. Scan to each object to be imaged It shines and it will, and further comprising a second partial image and the fourth image forming step of performing repeatedly the process of forming the image forming object.

  In the first image forming apparatus and method of the present invention, the predetermined part of the first partial image and the predetermined part of the second partial image are overlapped to form the first partial image and the second part. An image composed of the image is formed on the image forming target. Specifically, first, the light corresponding to each of the plurality of block images constituting the first partial image is scanned in the first direction to irradiate the object to be imaged. Are formed on the image formation target, and then scanned in a second direction opposite to the first direction to irradiate each of the image formation targets, whereby the first partial image is formed. The first process for forming the image forming target is repeatedly executed. Substantially in synchronization with this first processing, the light corresponding to each of the plurality of block images constituting the second partial image is first scanned in the second direction to irradiate the image formation target. Then, the second partial image is formed on the image formation target, and then the second partial image is scanned by irradiating each of the image formation targets by scanning in the first direction. The second process to be formed on the formation target is repeatedly executed.

  The second image forming apparatus of the present invention is an image forming apparatus for forming an image on an image forming target, and firstly applies light corresponding to each of a plurality of block images constituting the image in a first direction. To form an image on the image forming target, and then scan in the second direction opposite to the first direction to form the image. By irradiating each of the objects, the first image forming unit that repeatedly executes the process of forming the image on the image forming target and the same image are formed almost in synchronization with the first image forming unit. First, the light corresponding to each of the plurality of block images is scanned in the second direction to irradiate the image formation target, thereby forming the image on the image formation target, and then Scan the image in the first direction By going irradiated respectively to the subject, characterized in that it comprises a second image forming means for repeatedly executing the processing for forming the image on an image forming object.

  The second image forming method of the present invention is an image forming method corresponding to the above-described third image forming apparatus of the present invention, in which light corresponding to each of a plurality of block images constituting the image is firstly introduced. The image is formed on the image forming target by scanning in the first direction and irradiating the image forming target, and then scanning in the second direction opposite to the first direction. The first image forming step for repeatedly executing the process of forming the image on the image forming target by irradiating each of the image forming target with the first image forming step, First, light corresponding to each of a plurality of block images constituting the same image is scanned in the second direction to irradiate the image formation target, thereby forming the image on the image formation target. Then run in the first direction To that will irradiating respectively the image forming object, characterized in that it comprises a second image forming step of performing repeatedly the process of forming an image on an image forming object.

  In the second image forming apparatus and method of the present invention, a predetermined image is formed on the image forming target. Specifically, the light corresponding to each of the plurality of block images constituting the predetermined image is first scanned in the first direction to irradiate the object to be imaged, and thereby the predetermined image is displayed. A predetermined image is formed on the image formation target by forming the image formation target and then irradiating the image formation target with scanning in a second direction opposite to the first direction. The first process is repeatedly executed. Substantially in synchronization with this first processing, the light corresponding to each of the plurality of block images constituting the same predetermined image is first scanned in the second direction and irradiated onto the object to be imaged. In this way, a predetermined image is formed on the image forming target, and then the predetermined image is formed on the image forming target by scanning in the first direction and irradiating the image forming target respectively. The second process is repeatedly executed.

  The third image forming apparatus of the present invention superimposes a predetermined part of the first partial image and a predetermined part of the second partial image, so that the first partial image and the second partial image An image forming apparatus for forming an image formed of an image forming target on a target to be imaged, wherein light corresponding to each of a plurality of block images constituting the first partial image is first transmitted from the first start position to the first image. The first partial image is formed on the image forming target by scanning in the direction and irradiating the image forming target, and then the process of returning the scanning position to the first start position is repeatedly executed. The light corresponding to each of the plurality of block images constituting the second partial image is firstly transmitted from the second start position to the first image forming means and in synchronization with the first image forming means. Scan the image in the second direction opposite to the direction of A second image forming unit that repeatedly executes a process of forming the second partial image on the image formation target by irradiating the target and then returning the scanning position to the second start position; It is characterized by that.

  A third image forming method of the present invention is an image forming method corresponding to the above-described fifth image forming apparatus of the present invention, and the light corresponding to each of a plurality of block images constituting the first partial image. First, the first partial image is formed on the image formation target by scanning in the first direction from the first start position and irradiating the image formation target, respectively, and then the scan position. The first image forming step for repeatedly executing the process of returning the image to the first start position, and each of the plurality of block images constituting the second partial image substantially in synchronization with the processing of the first image forming step First, the corresponding partial light is scanned from the second start position in the second direction opposite to the first direction to irradiate the object to be imaged. Form the image to be imaged, and then set the scanning position. Characterized in that it comprises a second image forming step of repeatedly executing a process of returning to the second start position.

  In the third image forming apparatus and method of the present invention, the predetermined part of the first partial image and the predetermined part of the second partial image are overlapped to form the first partial image and the second part. An image composed of the image is formed on the image forming target. Specifically, the light corresponding to each of the plurality of block images constituting the first partial image is first scanned from the first start position in the first direction and irradiated to the object to be imaged. As a result, the first process for forming the first partial image on the image forming target and then returning the scanning position to the first start position is repeatedly executed. Substantially in synchronization with the first processing, light corresponding to each of the plurality of block images constituting the second partial image is first transmitted from the second start position in the direction opposite to the first direction. The second process of forming the second partial image on the image forming target by scanning in the direction 2 and irradiating the image forming target respectively, and then returning the scanning position to the second start position Is repeatedly executed.

  As described above, according to the present invention, by scanning a light beam corresponding to a part of a predetermined image, the predetermined image can be formed as an image formation target. In particular, the predetermined image can be formed on the image formation target as a clear image that does not feel uncomfortable for the observer.

  Embodiments of the present invention will be described below. Correspondences between constituent elements described in the claims and specific examples in the embodiments of the present invention are exemplified as follows. This description is to confirm that specific examples supporting the invention described in the claims are described in the embodiments of the invention. Therefore, even though there are specific examples that are described in the embodiment of the invention but are not described here as corresponding to the configuration requirements, the specific examples are not included in the configuration. It does not mean that it does not correspond to a requirement. On the contrary, even if a specific example is described here as corresponding to a configuration requirement, this means that the specific example does not correspond to a configuration requirement other than the configuration requirement. not.

  Further, this description does not mean that all the inventions corresponding to the specific examples described in the embodiments of the invention are described in the claims. In other words, this description is an invention corresponding to the specific example described in the embodiment of the invention, and the existence of an invention not described in the claims of this application, that is, in the future, a divisional application will be made. Nor does it deny the existence of an invention added by amendment.

According to the present invention, a first image forming apparatus is provided. The first image forming apparatus (for example, the image forming apparatus 1 of FIG. 1 and applied with a reverse scan tiling technique based on a reciprocating scan described later with reference to FIG. 9)
A predetermined part (for example, the blending area 61 in FIG. 9) of the first partial image (for example, the partial image 51-1 in FIG. 9) and a predetermined part of the second partial image (for example, the partial image image 51-2 in FIG. 9). Is overlapped with a part (for example, the blending area 61 in FIG. 9), so that an image composed of the first partial image and the second partial image is an image formation target (for example, an image formation target part in FIG. 1). 14) an image forming apparatus to be formed;
First, light corresponding to each of a plurality of block images constituting the first partial image is scanned in a first direction (for example, from the right to the left) to irradiate the object to be imaged. Thus, the first partial image is formed on the image forming target, and then scanned in a second direction opposite to the first direction (for example, from left to right) to form the imaged object. By irradiating each target, the process of forming the first partial image on the image forming target is repeatedly executed (for example, as shown in the timing chart below the partial image 51-1 in FIG. 9). First image forming means (for example, the image forming unit 13-1 in FIG. 1),
The image formation is performed by first scanning light corresponding to each of a plurality of block images constituting the second partial image in the second direction substantially in synchronization with the first image forming means. By irradiating each of the objects, the second partial image is formed on the object to be imaged, and then scanned in the first direction to irradiate each object to be imaged. Secondly, a process of forming the second partial image on the image formation target is repeatedly executed (for example, a process as shown in a timing chart below the partial image 51-2 in FIG. 9 is executed) And image forming means (for example, the image forming unit 13-2 in FIG. 1).

  In addition, according to the present invention, there is provided a 1-2 image forming apparatus in which the above-described first image forming apparatus is combined with the following second image forming apparatus. That is, the 1-2 image forming apparatus can be configured as, for example, the image forming apparatus 1 in FIG. 1 and includes the reverse scan tiling technique applied to the above-described first image forming apparatus of the present invention. It can be configured as an image forming apparatus 1 to which a reverse scan stacking method applied to a second image forming apparatus of the present invention to be described later is applied. In this case, each of the first image forming unit to the fourth image forming unit can be configured as each of the image forming units 13-1 to 13-4 in FIG.

  Furthermore, according to the present invention, a first image forming method corresponding to the first image forming apparatus and a 1-2 image forming method corresponding to the 1-2 image forming apparatus are also provided. The

According to the present invention, a second image forming apparatus is provided. The second image forming apparatus (for example, the image forming apparatus 1 in FIG. 1 and the image forming apparatus 1 to which the reverse scan stacking method described later with reference to FIG. 13 is applied)
In an image forming apparatus for forming an image (for example, each of the frames 81-1 to 81-3 in FIG. 13) on an image forming target (for example, the image forming target portion 14 in FIG. 1),
The light corresponding to each of the plurality of block images constituting the image is first scanned in a first direction (for example, from the right to the left) to irradiate each of the image formation targets, An image is formed on the image formation target, and then scanned in a second direction (for example, left to right) opposite to the first direction to irradiate the image formation target, respectively. Thus, the process of forming the image on the image formation target is repeatedly executed (for example, the forward scanning is started from the right to the left at time t10 in FIG. 13, and then the process is executed in accordance with the timing chart in FIG. ) First image forming means (for example, image forming unit 13-1 in FIG. 1);
The light corresponding to each of a plurality of block images constituting the same image is first scanned in the second direction in synchronization with the first image forming means to be the image formation target. By irradiating each of the images, the image is formed on the object to be imaged, and thereafter, scanning the image in the first direction to irradiate each of the objects to be imaged, thereby causing the image to be imaged. Second image forming means that repeatedly executes the process to be formed on the image forming target (for example, starts the forward scan from the left to the right at time t10 in FIG. 13 and then executes the process according to the timing chart in FIG. 13). (For example, the image forming unit 13-2 in FIG. 1).

  According to the present invention, a second image forming method corresponding to the second image forming apparatus is also provided.

According to the present invention, a third image forming apparatus is provided. This third image forming apparatus (for example, the image forming apparatus 1 in FIG. 1 and to which the reverse scan tiling method based on the one-side scan described later with reference to FIG. 18 is applied)
A predetermined part (for example, blending area 61 in FIG. 18) of the first partial image (for example, partial image 51-1 in FIG. 18) and a predetermined part of the second partial image (for example, partial image image 51-2 in FIG. 18). Is overlapped with a part (for example, the blending area 61 in FIG. 18), so that an image composed of the first partial image and the second partial image is an image formation target (for example, an image formation target part in FIG. 1). 14) an image forming apparatus to be formed;
First, the light corresponding to each of the plurality of block images constituting the first partial image is scanned in the first direction (for example, from right to left) from the first start position, and the image formation target , The first partial image is formed on the image formation target, and then the process of returning the scanning position to the first start position is repeatedly executed (for example, the portion of FIG. 18). A first image forming unit (for example, the image forming unit 13-1 in FIG. 1) that executes processing as shown in the timing chart below the image 51-1,
The light corresponding to each of the plurality of block images constituting the second partial image is first synchronized with the first image forming means from the second start position to the first direction. The second partial image is formed on the image forming target by scanning in the second direction opposite to the target and irradiating the image forming target, and then the scan position is set to the second target. A second image forming unit (for example, the image forming unit in FIG. 1) that repeatedly executes the process of returning to the start position (for example, performs the process as shown in the timing chart below the partial image 51-2 in FIG. 18). And 13-2).

  According to the present invention, a third image forming method corresponding to the third image forming apparatus is also provided.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration example of an image forming apparatus to which the present invention is applied.

  In the example of FIG. 1, the image forming apparatus 1 includes N (N is an integer value of 1 or more) image signal output units 11-1 to 11 -N, a blending processing unit 12, and image forming units 13-1 to 13. -N and an image forming target portion 14.

  The image forming apparatus 1 can form an entire image on the image forming target portion 14 by performing an operation (processing) corresponding to the above-described tiling method or stacking method. The entire image formed by the image forming apparatus 1 is an image in which the above-described conventional first and second problems are not generated. If the second problem is focused on and expressed accurately, the entire image formed by the image forming apparatus 1 is an image in which the degree of occurrence of the second problem is reduced, as will be described later, that is, The image is reduced in the degree of occurrence of the double image state. That is, the image forming apparatus 1 is applied with a conventional technique for solving the first problem and the second problem. However, a conventional technique for solving the first problem and the second problem will be described later with reference to FIGS.

  Each of the image signal output units 11-1 to 11-N is configured as a video playback device that plays back video recorded on a predetermined recording medium such as a video tape or a DVD (Digital Versatile Disk). Each of the image signal output units 11-1 to 11-N provides the blending processing unit 12 with an image signal corresponding to a predetermined one of several partial images constituting the entire image.

  The blending processing unit 12 performs a blending process on each of the N image signals provided from each of the image signal output units 11-1 to 11-N, and each of the N image signals after the blending process is performed. Provided to each of the image forming units 13-1 to 13-N.

  The blending process is, for example, the blending region or its vicinity so that the blending region in which one partial image and another partial image are superimposed or the image in the vicinity thereof becomes a natural image that does not feel strange to the observer. The process performed with respect to the image signal corresponding to this image. For example, in the present embodiment, a blending area 61 in a partial image 51-1 shown in FIG. 8 to be described later is a gradation-like image shown on the rightmost side at time t1 on the time axis in FIG. A process for correcting the luminance level of the corresponding image signal is employed as a blending process. Needless to say, this blending process of the present embodiment is just one example of various blending processes. That is, the content of the blending process executed by the blending processing unit 12 is not particularly limited.

  Each of the image forming units 13-1 to 13 -N is configured as a projector, for example, and the image signal provided from the blending processing unit 12 (corresponding one of N image signals output from the blending processing unit 12). 1D image light fluxes are generated on the basis of the one-dimensional image light fluxes, and the one-dimensional image light fluxes are scanned in a predetermined scanning direction (vertical direction in the example of FIG. By irradiating (projecting), one corresponding partial image is formed at a corresponding position on the image forming target portion 14. Further details of the image forming units 13-1 to 13-N will be described later with reference to FIGS.

  In this way, several partial images (for example, partial images 51-2 to 51-3 in FIG. 9 to be described later) are respectively obtained by the image forming units 13-1 to 13-N in the image forming target portion 14. As a result, a whole image (for example, a whole image 71 in FIG. 9 described later) composed of these several partial images is formed. Such an image forming target portion 14 is constituted by a screen or the like when the image forming portions 13-1 to 13-N are constituted by projectors, for example.

  The image forming target portion 14 is not a particularly essential component for the image forming apparatus 1. This is because, when the image forming units 13-1 to 13-N are configured by projectors, for example, these projectors can directly form an image on a white wall or the like.

  Next, the details of the image forming units 13-1 to 13-N in the image forming apparatus 1 will be described with reference to FIGS.

  In the present embodiment, the image forming units 13-1 to 13-N all have the same function and the same configuration. Therefore, hereinafter, when it is not necessary to individually distinguish the image forming units 13-1 to 13-N, one of them is simply referred to as an image forming unit 13. When the image forming unit 13 is referred to, the image forming unit 13 (the predetermined one of the image forming units 13-1 to 13-N) of the image signal output units 11-1 to 11-N. ) Is simply referred to as an image signal output unit 11.

  FIG. 2 shows a detailed configuration example of the image forming unit 13. In the example of FIG. 2, the image forming unit 13 includes a central control unit 21 to an operation unit 28.

  The central control unit 21 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The central control unit 21 controls the overall operation of the image forming unit 13 based on the operation content of the operation unit 28 by the user and the judgment of the central control unit 21 itself.

  For example, when the setting information related to the scanner 26 set by the user is provided from the operation unit 28, the central control unit 21 sets the projection mode of the scanner 26 based on the setting information, and the forward direction of the scanner 26 By setting (the forward scanning direction), the operation of the scanner 26 is controlled.

  Here, the setting of the projection mode and the setting of the forward direction will be described.

  That is, as will be described later, the scanner 26 has a scan mirror 26a (see FIG. 4), and the one-dimensional image light beam is scanned in the forward direction by rotating the scan mirror 26a back and forth within a predetermined range. After that, a scanning operation (hereinafter referred to as a reciprocating scan) of scanning in the reverse direction of the reverse direction can be performed. Hereinafter, the projection mode in which the reciprocating scan is executed is referred to as a reciprocating mode.

  Further, the scanner 26 scans a one-dimensional image light beam only in the forward direction and prohibits scanning in the backward direction when the scan mirror 26a is reciprocally rotated within a predetermined range (hereinafter referred to as one-side scan). Can also be executed. Hereinafter, the projection mode in which the one-side scan is executed is referred to as a one-side mode.

  Thus, in the present embodiment, the reciprocating mode and the one-side mode are provided as the projection modes. Therefore, in the present embodiment, the central control unit 21 can select and set either the reciprocal mode or the one-side mode as the projection mode in the scanner 26.

  In the present embodiment, the scanner 26 has a first direction (for example, a direction from bottom to top in FIG. 2 and a direction from left to right in FIG. 3 to be described later) as the forward direction, and Is configured to be able to set any of the opposite second directions (for example, a direction from top to bottom in FIG. 2 and a direction from right to left in FIG. 3 described later). Therefore, in the present embodiment, the central control unit 21 can select and set one of the first direction and the second direction as the forward direction in the scanner 26.

  Specifically, in the present embodiment, for example, the central control unit 21 selects the projection mode and the forward direction in this way, and then provides the selection contents to the scanner 26 as a scanner setting command SD. The projection mode and the forward direction can be set.

  Further, for example, the central control unit 21 is provided with scan position information SAS indicating the rotation angle of the scan mirror 26a of the scanner 26 from the scanner control unit 27, or a video synchronization signal of the input video signal (synchronizing each frame). Signal) FRMsync is provided from the image processing unit 22.

  Therefore, the central control unit 21 generates a scan command SIS based on the scan position information SAS, the video synchronization signal FRMsync, and the like, and provides the scan command SIS to the scanner control unit 27, for example. As a result, the scanning operation of the scanner 26 is controlled via the scanner control unit 27. The scan command SIS means basic data for driving the scan mirror 26a of the scanner 26, and information including phase information, amplitude information, period information, and the like.

  For example, the central control unit 21 generates the timing command RQT based on the video synchronization signal FRMsync or the like. The timing command RQT is a command for instructing the output timing of the drive signal to the GLV module 24. The central control unit 21 controls the operation of the drive timing control unit 23 by providing the timing command RQT to the drive timing control unit 23.

  Further, for example, the central control unit 21 provides the image processing unit 22 with the projection mode and the forward direction of the scanner 26 included in the scan command SIS as the projection direction command PD. Control.

  The video signal output from the blending processing unit 12 in FIG. 1 is input to the image processing unit 22 as an input video signal. Therefore, the image processing unit 22 performs a predetermined process on the input video signal, thereby generating a video signal in units of a one-dimensional image that is also a scan unit of the scanner 26, and provides the video signal to the drive timing control unit 23. .

  At that time, the image processing unit 22 recognizes the forward direction from the projection direction command PD, and changes the order of the signals of the pixels constituting the input video signal with respect to the video synchronization signal FRMsync based on the recognition result. Can do. Note that a detailed example of how to change the order of signals of each pixel will be described later with reference to FIGS.

  Further, the image processing unit 22 recognizes the projection mode from the projection direction command PD, and when the recognition result is the reciprocal mode, for example, the frequency of the video synchronization signal FRMsync can be doubled. Note that the frequency of the video synchronization signal FRMsync may be tripled as will be described later with reference to FIG. That is, the image processing unit 22 can arbitrarily change the frequency of the video synchronization signal FRMsync.

  The drive timing control unit 23 converts the video signal supplied from the image processing unit 22 into a drive signal (drive voltage) for driving the GLV module 24 in units of one-dimensional images, and performs primary processing according to the timing command RQT. The drive signal of the original image unit is sequentially provided to the GLV module 24.

  The GLV (Gratingu Light Valve) module 24 is configured by one-dimensionally arranging GLV elements corresponding to each of a plurality of pixels (for example, 1080 pixels in the present embodiment). When a driving voltage of each GLV element corresponding to the one-dimensional image to be scanned is provided as a driving signal from the driving timing control unit 23, a corresponding driving voltage is applied to each GLV element, and as a result, not shown. Incident light (illumination light) is reflected or diffracted, and the resulting reflected light or diffracted light is emitted to the projection optical system 25. The reflected light or diffracted light emitted from the GLV module 24 in this way becomes a one-dimensional image light beam to be scanned, which is composed of the number of GLV elements (1080 in the present embodiment). That is, the GLV module 24 emits a one-dimensional image light beam to be scanned to the projection optical system 25 when a drive signal for the one-dimensional image to be scanned is supplied from the drive timing control unit 23. In other words, the GLV module 24 is a modulation unit that optically modulates the drive signal (voltage).

  The projection optical system 25 converts the scan target one-dimensional image light beam emitted from the GLV module 24 into parallel light, and ± 1st-order analysis light itself of the parallel light itself or a predetermined method thereof. The processed light is emitted to the scanner 26.

  The scanner 26 includes a scan mirror 26a shown in FIG. 4 to be described later, a scanner motor (not shown) that reciprocally rotates the scan mirror 26a, and the like. The scan mirror 26a reflects the one-dimensional image light beam emitted from the projection optical system 25 and projects the reflected light onto the image forming target portion 14 shown in FIG. As a result, a one-dimensional image to be scanned is formed (formed) at a predetermined position of the image forming target portion 14. At this time, since the scan mirror 26a is reciprocatingly rotated by the scanner motor, each of the plurality of one-dimensional image light beams sequentially emitted from the projection optical system 25 corresponds to the imaged image according to the rotational position of the scan mirror 24a. The projection is sequentially performed on the corresponding position of the formation target portion 14 (hereinafter referred to as a scan position). That is, the scanner 26 sequentially scans each of the plurality of one-dimensional image light beams sequentially emitted from the projection optical system 25 in the scanning direction and sequentially projects them on the corresponding scan positions of the image forming target portion 14. As a result, a two-dimensional image formed by arranging the plurality of one-dimensional images in the scanning direction is formed on the image forming target portion 14. The details of the scanning operation of the scanner 26 will be described later with reference to FIGS.

  The scanner control unit 27 generates a drive signal SDS for rotating the scanner motor of the scanner 26 based on the scan command SIS, and provides it to the scanner motor of the scanner 26. Further, the scanner control unit 27 detects the rotation angle (rotation position) of the scanner motor, generates scan position information SAS based on the detection result, and provides it to the central control unit 21. Therefore, although not shown, the scanner control unit 27 can be configured to include, for example, a drive device that outputs the drive signal SDS to the scanner motor and a detection sensor that detects the rotation angle of the scanner motor.

  Next, the scanning operation of the image forming unit 13 having such a configuration will be described with reference to FIGS. 3 to 7.

  FIG. 3 shows a projection plane when the image forming target portion 14 of FIG. 1 is configured as a screen. Each of numerical values 1 to 1920 described below the image forming target portion 14 indicates a one-dimensional image number. Further, the arrow below it indicates the scanning direction. That is, although details will be described later, in the example of FIG. 3, the one-dimensional images having numbers 1 to 1920 each have the corresponding numerical values in FIG. 3 on the projection plane of the image forming target portion 14. The images are sequentially projected on the positions in the order or in the reverse order. As a result, 1920 two-dimensional images (see FIG. 5 described later) are formed on the projection surface of the image forming target unit 14. .

  FIG. 4 is a diagram for schematically explaining the scanning operation of the scan mirror 26a of the scanner 26 of FIG.

  As shown in FIG. 4, the scan mirror 26a sequentially reflects each of a plurality of one-dimensional image light beams projected sequentially from the projection optical system 25 of FIG. 2 while rotating back and forth within a predetermined angle range. Then, each reflected light beam is sequentially irradiated to the corresponding scan position on the projection surface of the image forming target portion 14.

  Specifically, for example, in the example of FIG. 4, the rotation operation in which the scan mirror 26a rotates in the order of the rotation positions c, b, and a is the forward rotation operation. When the scanning mirror 26a performs the forward rotation operation, that is, when the scanning mirror 26a sequentially rotates and moves to each of the rotation positions c, b, a, a one-dimensional image projected from the projection optical system 25 at each time point. The light beams are sequentially reflected by the scan mirror 26a, and the reflected light beams Lc, Lb, and La are sequentially irradiated onto the corresponding scan positions on the projection surface of the image forming target portion 14. That is, in the example of FIG. 4, the direction from right to left is the forward direction.

  Similarly, in the example of FIG. 4, the rotation operation in which the scan mirror 26 a rotates in the order of the rotation positions a, b, and c is defined as the return path rotation operation. When the scan mirror 26a performs the rotation of the return path, that is, when the scan mirror 26a sequentially rotates to each of the rotation positions a, b, and c, the one-dimensional image projected from the projection optical system 25 at each time point. The light beams are sequentially reflected by the scan mirror 26a, and the reflected light beams La ′, Lb ′, and Lc ′ are sequentially irradiated onto the corresponding scan positions on the projection surface of the image forming target portion 14. That is, in the example of FIG. 4, the direction from left to right is the return direction.

  In FIG. 4, in order to clarify the difference between the forward path and the return path, each of the reflected lights La, Lb, and Lc and a position different from each of the reflected lights La ′, Lb ′, and Lc ′ are scan positions. Although it is depicted to be (irradiated position), actually, when the rotation position of the scan mirror 26a is the same position, the forward scan position and the backward scan position coincide. However, more precisely, the scan position on the forward path and the scan position on the backward path coincide with each other only when the technique disclosed in Patent Document 1 described above is used.

  In this way, the scan mirror 26a reciprocally rotates within a predetermined angle range while reflecting each of a plurality of one-dimensional image light beams sequentially projected from the projection optical system 25 and receiving each reflected light beam. By sequentially irradiating the corresponding scan positions on the projection surface of the image forming target unit 14, for example, a two-dimensional image as shown in FIG. 5 is formed on the projection surface of the image forming target unit 14. That is, FIG. 5 shows an example of a two-dimensional image formed on the projection surface of the image forming target portion 14 by the scanning operation of the scan mirror 26a.

  In the example of FIG. 5, when the scan mirror 26a is positioned at the rotational position a, the position A in the left-right direction of the projection surface of the image forming target 14 is the scan position, and is one-dimensional based on the reflected light beam La or La ′. An image 31a is formed at position A. Note that. Hereinafter, one one-dimensional image formed on the projection surface of the image forming target portion 14 is referred to as a line. That is, the line 31a is formed at the position A on the projection surface of the image forming target portion 14. Similarly, when the scan mirror 26a is located at the rotation position b, the position B in the left-right direction of the projection surface of the image forming target 14 becomes the scan position, and the one-dimensional image 31b based on the reflected light beam Lb or Lb ′ is obtained. Formed at position B. When the scan mirror 26a is positioned at the rotation position c, the position C in the left-right direction of the projection surface of the image forming target portion 14 is the scan position, and the one-dimensional image 31c based on the reflected light beam Lc or Lc ′ is positioned. Formed in C.

  Therefore, in the example of FIG. 5, since one line is composed of 1080 pixels, eventually, the size of 1920 lines in the horizontal direction and 1080 pixels in the vertical direction (hereinafter, this size is referred to as 1920 × 1080). 2D image is formed on the projection surface of the image forming target portion 14.

  Further, the scanning operation of the image forming unit 13 will be described below with reference to FIGS. 6 and 7.

  That is, as described above, the image forming unit 13 can be variably set in the forward direction. Specifically, for example, in the example of FIGS. 3 to 5 described above, the image forming unit 13 has both the direction from left to right as the forward direction and the opposite direction, that is, the direction from right to left. Can be set. FIG. 6 is a diagram for explaining the scanning operation of the image forming unit 13 when the forward direction is set from left to right. On the other hand, FIG. 7 is a diagram for explaining the scanning operation of the image forming unit 13 when the forward direction is set from the right to the left.

  For this reason, in FIGS. 6 and 7, the one-dimensional image light beam from the scanner 26 in FIG. 2 in the scan position (from the projection surface of the image forming target portion 14 in FIG. The timing chart of each of the current position being projected), the video signal output from the image processing unit 22, and the video synchronization signal FRMsync output from the image processing unit 22 is shown.

  6 and 7, reference numerals 1 to 1920 described on the video signal indicate the same line numbers as in FIG. That is, the pulse below the line number k (k is 1 to 1920) indicates the video signal for the line (kinematic dimension) of the line number k. Further, one pulse of the video synchronization signal FRMsynk is a pulse indicating the start of a predetermined one frame (a two-dimensional image of 1920 × 1080). However, here, it is assumed that the frequency of the video synchronization signal FRMsynk is twice the normal frequency (60 [Hz] which is the frame rate), that is, 120 [Hz]. In other words, it is assumed that a pulse indicating the start of the same frame is continuously output twice during the normal frame rate of 60 [Hz]. As will be described later, this is because the image forming unit 13 causes the image forming target unit 14 to form the same frame for both the scanning in the forward direction and the scanning in the backward direction.

  Hereinafter, the scanning operation of the image forming unit 13 when the forward direction is set from the left to the right will be described first with reference to FIG. 6, and the forward direction is set to the right with reference to FIG. The scanning operation of the image forming unit 13 when set in the direction from left to left will be described.

  As shown in the bottom timing chart in FIG. 6, when the pulse of the video synchronization signal FRMsync is raised, the central control unit 21 in FIG. 2 determines that the start of projection of a predetermined first frame has been instructed, 4 controls the forward rotation operation of the scan mirror 26a described in FIG. 4 (note that it is indicated as the return path in the example of FIG. 4), and the first timing from the drive timing control unit 23. The output timing of the drive signal for the frame is controlled.

  Then, as shown in the top timing chart in FIG. 6, the scan position is changed from the left end (position where the number 1 line is formed) to the right end (number 1920 line) of the projection surface of the image forming target portion 14. Are sequentially moved to the position where the is formed.

  During this time, as shown in the second timing chart from the top in FIG. 6, the image processing unit 22 sequentially outputs video signals for each of the numbers 1 to 1920 constituting the first frame in that order. It will be output.

  Thereby, between the left end and the right end of the projection surface of the image forming target portion 14, a two-dimensional image composed of each line of numbers 1 to 1920, specifically, for example, one line is composed of 1080 pixels. In such a case, a two-dimensional image as shown in FIG. 5 is formed. That is, the first frame is projected onto the image forming target portion 14 by scanning in the forward direction.

  Next, as shown in the timing chart at the bottom in FIG. 6, when the pulse of the video synchronization signal FRMsync is raised, the central control unit 21 reverses the rotation operation of the scan mirror 26a and then performs the rotation operation ( However, in the example of FIG. 4, it is necessary to pay attention to the fact that it is shown as the forward path), and the output timing of the drive signal for the first frame from the drive timing control unit 23 is continuously controlled.

  Then, as shown in the uppermost timing chart in FIG. 6, the scan position sequentially moves from the right end to the left end of the projection surface of the image forming target portion 14.

  During this time, as shown in the second timing chart from the top in FIG. 6, the image processing unit 22 now receives video signals for the respective lines of line numbers 1 to 1920 constituting the first frame. The data is output sequentially in the reverse order. That is, this time, the video signals for each of the lines with line numbers 1920 to 1 are sequentially output in that order.

  Thereby, between the right end and the left end of the projection surface of the image formation target portion 14, a two-dimensional image composed of each line number 1920 to 1, specifically, for example, one line is composed of 1080 pixels. In such a case, a two-dimensional image as shown in FIG. 5 is formed. That is, the first frame is also projected onto the image forming target portion 14 by scanning in the backward direction.

  For the second frame to the Fth frame (F is an integer value of 2 or more) after the first frame, the above-described scanning operation is repeatedly performed in the same way, so Projected sequentially.

  In contrast to the scanning operation of the image forming unit 13 when the forward direction is set from the left to the right, the scanning of the image forming unit 13 when the forward direction is set from the right to the left. The operation is as shown in FIG.

  That is, as shown in the timing chart at the bottom in FIG. 7, when the pulse of the video synchronization signal FRMsync rises, the central control unit 21 determines that the start of projection of a predetermined first frame is instructed, and scans The mirror 26a controls, for example, the forward rotation operation (the forward path here coincides with the forward path in the example of FIG. 4), and the output timing of the drive signal for the first frame from the drive timing control unit 23 is controlled. Control.

  Then, as shown in the uppermost timing chart in FIG. 7, the scan position sequentially moves from the right end to the left end of the projection surface of the image forming target portion 14.

  Meanwhile, as shown in the second timing chart from the top in FIG. 6, the image processing unit 22 determines that the video signals for each of the lines numbered 1 to 1920 constituting the first frame are in that order. It is output sequentially in the reverse order. That is, the video signals for each of the numbers 1920 to 1 are sequentially output in that order.

  Thereby, between the right end and the left end of the projection surface of the image forming target portion 14, a two-dimensional image composed of each of the numbers 1920 to 1, specifically, for example, one line is composed of 1080 pixels. In such a case, a two-dimensional image as shown in FIG. 5 is formed. That is, the first frame is projected onto the image forming target portion 14 by scanning in the forward direction.

  Next, as shown in the timing chart at the bottom of FIG. 7, when the pulse of the video synchronization signal FRMsync is raised, the central control unit 21 reverses the rotation operation of the scan mirror 26a and then rotates the return path ( The return path here corresponds to the return path in the example of FIG. 4), and the output timing of the drive signal for the first frame from the drive timing control unit 23 is continuously controlled.

  Then, as shown in the top timing chart in FIG. 7, the scan position sequentially moves from the left end to the right end of the projection surface of the image forming target portion 14.

  During this time, as shown in the second timing chart from the top in FIG. 7, the image processing unit 22 now outputs video signals for each of the numbers 1 to 1920 constituting the first frame. Output sequentially in order

  Thereby, between the left end and the right end of the projection surface of the image forming target portion 14, a two-dimensional image composed of each line of numbers 1 to 1920, specifically, for example, one line is composed of 1080 pixels. In such a case, a two-dimensional image as shown in FIG. 5 is formed. That is, the first frame is also projected onto the image forming target portion 14 by scanning in the backward direction.

  The second to Fth frames after the first frame are also sequentially projected onto the image forming target portion 14 by repeating the above scanning operation in exactly the same manner.

  The scanning operation of the image forming unit 13 has been described above with reference to FIGS.

  Next, with reference to the drawings from FIG. 8 onward, the above-described operations (processes) of the image forming apparatus 1 of FIG. 1 in which the image forming units 13-1 to 13-N performing the scanning operation are mounted are described above. Operations corresponding to the stacking method and the tiling method will be described.

  First, an example of an operation corresponding to the tiling method will be described with reference to FIGS. 8 and 9.

  In the example of FIGS. 8 and 9, the image forming apparatus 1 is assumed to be equipped with three image forming units 13-1 to 13-3.

  In this case, in the example of FIGS. 8 and 9, the partial images 51-1 to 51-3 are respectively formed on the projection surface of the image forming target unit 14 by the image forming units 13-1 to 13-3. As a result, the entire image 71 is formed. The overlapping portion of the partial image 51-1 and the partial image 51-2 at this time, that is, the blending region is the region 61. In addition, the overlapped portion of the partial image 51-2 and the partial image 51-3 at this time, that is, the blending region is set as a region 62. Each of the partial images 51-1 to 51-3 is a black and white image (an image having only one luminance value as a pixel value), and the pixel values of all the pixels have the same value R (R is For example, in the case of 246 gradations, an image having an integer value of 0 to 245), that is, an image of a gray surface having a predetermined density.

  8 and 9, timing charts of the scan positions of the image forming units 13-1 to 13-3 are shown below the partial images 51-1 to 51-3, respectively. One timing chart for each of the image forming units 13-1 to 13-3 is basically the same as the timing chart at the top of FIG. 6 or FIG. 7 (more precisely, the timing chart inverted 90 degrees). Since it is the same, the description is omitted here.

  In the example of FIGS. 8 and 9, a blending region 61 (two-dimensional image) in the time zone near the times t1 to t7 is shown on the right side of the timing chart. This blending area 61 is an image in which the right side portion of the partial image 51-1 formed by the image forming unit 13-1 and the left side portion of the partial image 51-2 formed by the image forming unit 13-2 are superimposed. It is. Therefore, hereinafter, the right side portion of the partial image 51-1 formed by the image forming unit 13-1 and the left side portion of the partial image 51-2 formed by the image forming unit 13-2 are specifically referred to as blended images. . As described above, this blended image is shown in FIGS. 8 and 9 after the blending processing unit 12 in FIG. 1 has processed the entire gray surface (all pixels having a uniform pixel value R). In such a horizontal direction, the gray density (pixel value) becomes a gradation image.

  More specifically, when focusing on one predetermined image forming unit 13-K (where K is one of 1 to 3 in the examples of FIGS. 8 and 9), the blended image is a partial image. The direction of the gradation is made different depending on whether it is formed on the right side of 51-K or on the left side. Specifically, in the example of FIGS. 8 and 9, for example, when the blended image is formed on the right side of the partial image 51-K by the image forming unit 13-K, the blended image is gray in the direction from the left to the right. The image becomes such that the image density decreases (the leftmost is the darkest and the rightmost is the lightest). Hereinafter, such a blended image is referred to as a first blended image. On the other hand, when the blended image is formed on the left side of the partial image 51-K by the image forming unit 13-K, the gray density of the blended image increases in the direction from left to right (first). (The left side is the thinnest and the right side is the darkest). Hereinafter, such a blended image is referred to as a second blended image.

  In the example of FIG. 8, the forward directions of the image forming units 13-1 to 13-3 are all set to the same direction, that is, the direction from right to left.

  In other words, it can be said that FIG. 8 is nothing but a diagram illustrating an operation in which the three conventional projectors whose forward directions are fixed in the direction from right to left form the entire image 71 on the screen or the like. In other words, FIG. 8 is a diagram for explaining an example of an operation corresponding to the conventional tiling technique having the first problem.

  Therefore, in the example of FIG. 8, the first problem described above, that is, the problem that the blending areas 61 and 62 in the entire image 71 are visually recognized as flickers occurs.

  The inventor has found that the cause of the first problem is as follows.

  That is, paying attention to the times t1 to t7 when the scanning direction is reversed, the scanning position of the image forming unit 13-1 is in the forming position of the blending region 61 in the time zone near the times t1, t3, t5, and t7. However, the scan position of the image forming unit 13-2 is not included in the blending area 61 formation position. Accordingly, only the first blended image that is the right portion of the partial image 51-1 formed by the image forming unit 13-1 becomes the blending region 61 in the time zone near the times t 1, t 3, t 5, and t 7.

  On the other hand, in the time zone near the times t2, t4, and t6, the scan position of the image forming unit 13-1 is not included in the blending region 61, but the scan position of the image forming unit 13-2 is The blending region 61 is formed. Therefore, only the second blended image that is the left portion of the partial image 51-2 formed by the image forming unit 13-2 becomes the blending region 61 in the time zone near the times t2, t4, and t6.

  Further, since the frame rate is 60 [Hz], the time intervals of the times t1 to t7 at which the scanning direction is reversed are expressed in terms of frequency as 120 [Hz] as shown in FIG.

  Accordingly, as the blending area 61, two different images such as the first blended image and the second blended image are projected with a cycle of 120 [Hz]. This is the cause of the first problem. Although not shown and described, this is exactly the same for the blending area 62.

  Therefore, the present inventor has invented the following tiling technique in order to solve the first problem.

  In other words, the conventional tiling technique is a tiling technique that uses a plurality of projectors in which the forward direction (the scanning direction of the forward path) is fixed in the same direction. On the other hand, the tiling method to which the present invention is applied is a method in which the forward directions of the two image forming units 13 that form the two partial images superimposed in the blending region are opposite to each other. is there. Hereinafter, such a tiling method to which the present invention is applied is referred to as a reverse scan tiling method.

  FIG. 9 is a diagram for explaining an example of an operation corresponding to such a reverse scan tiling method.

  Specifically, for example, in the example of FIG. 9, for the image forming unit 13-1 that forms the partial image 51-1 including the blending region 61 as the right side portion, the forward direction is the first direction from right to left. On the other hand, for the image forming unit 13-2 that forms the partial image 51-2 including the blending region 61 as the left side portion, the forward direction is set to the second direction from left to right. Similarly, for the image forming unit 13-2 that forms the partial image 51-2 including the blending region 62 as the right side portion, the forward direction is set to the second direction as described above. As for the image forming unit 13-3 that forms the partial image 51-3 including the left side portion, the forward direction is set to the first direction.

  Thereby, the first problem described above does not occur.

  That is, paying attention to the times t1 to t7 when the scanning direction is reversed, the scan position of the image forming unit 13-1 is in the formation position of the blending region 61 in the time zone near the times t1, t3, t5, and t7. In addition, the scan position of the image forming unit 13-2 is also included in the blending area 61 formation position. Accordingly, in the time zone near times t1, t3, t5, and t7, the first blended image that is the right side portion of the partial image 51-1 formed by the image forming unit 13-1, and the image forming unit 13-2. Are combined with the second blending image that is the left part of the partial image 51-2 formed by the above, and as a result, a gray-scale image having the same density (same luminance value R as other areas of the entire image 71). Becomes the blending region 61.

  Further, in the time zone near times t2, t4, and t6, the scan position of the image forming unit 13-1 is not within the forming position of the blending region 61, and the scan position of the image forming unit 13-2 is also the blending region. 61 is not in the formation position. Accordingly, nothing (excluding afterimages) is not projected on the formation position of the blending region 61 in the time zone near the times t2, t4, and t6.

  As described above, as the blending area 61, images of a gray surface having the same density, that is, the same image are sequentially projected at a period of 60 [Hz]. In other words, if the projection time (scan time) of the blending area 61 is sufficiently short, it is equivalent to the same image being projected onto the forming position of the blending area 61 at a frame rate of 60 [Hz]. Flicker does not occur in the area 61. That is, the first problem does not occur (is solved). Although not shown and described, this is exactly the same for the blending area 62.

  Next, an example of an operation corresponding to the stacking method will be described with reference to FIGS.

  10 to 13, the image forming apparatus 1 in FIG. 1 is assumed to have two image forming units 13-1 and 13-2. Further, it is assumed that the same frame is projected at the same position on the projection surface of the image forming target unit 14 by each of the two image forming units 13-1 and 13-2. That is, it is assumed that the scan ranges (scan position movement ranges) of the two image forming units 13-1 and 13-2 are the same.

  Further, in the example of FIGS. 10 to 13, the image 81-1 having the message “Ah” positioned in the lower right part is projected as the first frame on the projection surface of the image forming target unit 14, and then , The image 81-2 in which the message “ah” is located in the center portion is projected as the second frame, and the image 81-3 in which the message “ah” is located in the lower left portion is projected as the third frame. The That is, a moving image (video) in which the message “Ah” moves in the direction from right to left is projected onto the projection surface of the image forming target unit 14. At that time, the frame rate is set to 60 [Hz].

  In the example of FIGS. 10 and 13, the first frame 81-1 to the third frame 83-3 are shown in the order of projection. That is, in the example of FIG. 10 and FIG. 13, the projection of the first frame 81-1 is started at time t10, and the projection of the frame is switched at time t12 after 1/60 [s] has elapsed. The projection of 81-2 is started, and the projection of the frame is switched again at time t14 when 1/60 [s] has passed since then, and the projection of the third frame 81-2 is started.

  In the examples of FIGS. 10 and 13, the scan positions of the image forming units 13-1 and 13-2 are displayed on the right side of the first frame 81-1 to the third frame 81-3. A timing chart is shown. In the example of FIG. 10, it is depicted as if only one timing chart is shown, but this is because the timing charts of the respective scan positions of the image forming units 13-1 and 13-2 overlap. Because it is. The reason for overlapping will be described later.

  Furthermore, in the examples of FIGS. 10 and 13, on the right side of the timing chart, the image formation target at the times t10 to t16 of the first frame 81-1 to the third frame 81-3. A reduced view of the frame formed in the portion 14 is shown.

  In the example of FIG. 10, the forward directions of the image forming units 13-1 and 13-2 are both set to the same direction, that is, the direction from right to left. Therefore, as described above, the scan ranges of the image forming units 13-1 and 13-2 are the same, and each of the first frame 81-1 to the third frame 81-3 is approximately the same timing. Is started, the scan positions at the respective times of the image forming units 13-1 and 13-2 coincide with each other. That is, the timing charts of the scan positions of the image forming units 13-1 and 13-2 overlap. One timing chart for each of the image forming units 13-1 and 13-2 is basically the same as the top timing chart in FIG. 7 described above (more precisely, the timing chart inverted by 90 degrees). Therefore, the description thereof is omitted here.

  Accordingly, in the example of FIG. 10, a moving image equivalent to the case where the first frame 81-1 to the third frame 81-3 are sequentially projected by one image forming unit 13 is visually recognized by the observer. Will be. That is, FIG. 10 shows that, in the end, the conventional projector in which the forward direction is fixed in the direction from right to left displays the first frame 81-1 to the third frame 81-3 in that order. It can be said that there is nothing but a diagram for explaining the operation of sequentially forming them.

  Therefore, in the example shown in FIG. 10, the second problem described above, that is, the movement quickly in parallel with the scanning direction (moving in a short period of 3/60 = 1/20 [s] from the right to the left). ) The problem that the message “Ah” becomes a double-image state near the start point of scanning will occur as it is.

  The present inventor has found that the cause of the second problem is as follows.

  That is, for example, here, in the image forming target portion 14, a region where the left part of the first frame 81-1 to the third frame 81-3 is formed (a region surrounded by a one-dot chain line in FIG. 10). And is hereinafter referred to as a left-hand alternate long and short dash line region), a region where a central portion of the first frame 81-1 to the third frame 81-3 is formed (a region surrounded by a dotted line in FIG. 10). , Hereinafter referred to as a center dotted line region), and a region where the right part of the first frame 81-1 to the third frame 81-3 is formed (a region surrounded by a solid line in FIG. (Referred to as the right solid line region).

  The time zone in which the scan position of the conventional projector enters the left one-dot chain line region is a time zone near the times t11, t13, and t15. Therefore, in the time zone near time t11, the left portion of the first frame 81-1 overlaps and is projected onto the left one-dot chain line region. Next, in the time zone near time t13, as if the left side portion of the second frame 81-2 overlaps, it is projected onto the left one-dot chain line region. That is, an image 82 as shown in FIG. 11 is formed in the left one-dot chain line region. Returning to FIG. 10, in the time zone near time t15, the left portion of the third frame 81-3 overlaps and is projected onto the left one-dot chain line region. Accordingly, when the time intervals of the times t11, t13, and t15 are expressed in terms of frequency, the frequency is 60 [Hz] as shown in FIG. 10, and eventually, in the left-hand dashed line region, every frame rate of 60 [Hz]. Each frame (the left part thereof) is projected sequentially, and a double image state does not occur in particular.

  Further, the time zone in which the scan position of the conventional projector enters the central dotted line region is a time zone near the time between time t10 and time t16. That is, when the time interval of these time zones is expressed by frequency, it is 120 [Hz] as shown in FIG. Accordingly, during the period from time t10 to time t12, the central portion of the first frame 81-1 is sequentially projected onto the central dotted line area as if it were 120 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly. Similarly, during the period from time t12 to time t14, the central portion of the second frame 81-2 is successively projected onto the central dotted line area at intervals of 120 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly. Then, during the time t14 to t16, the central portion of the third frame 81-3 is sequentially projected onto the central dotted line area as if it were continuous at an interval of 120 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly.

  However, the time zone in which the scan position of the conventional projector enters the right solid line region, that is, the time zone of the time that is the scan start position of the conventional projector is a time zone in the vicinity of times t10, t12, t14, and t16. These times t10, t12, t14, and t16 are also timings at which the projection of each frame is switched (hereinafter referred to as frame switching timing). Accordingly, for example, in the vicinity of the time t12 that is the frame switching timing, that is, in the vicinity of the timing at which the projection is switched from the first frame 81-1 to the second frame 81-2, as shown in FIG. In addition, an image 83 (the right portion thereof) obtained by combining two different images such as the first frame 81-1 and the second frame 81-2 is projected onto the right solid line region. That is, as can be easily understood from the image 83, a double image state occurs in which two “Ah” messages whose arrangement positions are shifted are overlapped and viewed by the observer. Returning to FIG. 10, although not shown, even in the vicinity of the time t14 that is the frame switching timing, that is, in the vicinity of the timing at which the projection is switched from the second frame 81-2 to the third frame 81-3. The double image state occurs in exactly the same way. The double image state also occurs in the same manner in the time zone near the times t10 and t16, which are other frame switching timings.

  As described above, the time at which the conventional projector starts scanning is also the frame switching timing. As a result, an image in which two different frames before and after the switching are combined is displayed at a frame rate of 60 [Hz]. Are sequentially projected onto the right solid line region. This is the cause of the second problem.

  Therefore, the present inventor has invented the following stacking technique in order to solve the second problem.

  In other words, the stacking method to which the present invention is applied differs from the two image forming units 13 that form the same image at the same position of the image forming target unit 14 in their forward directions (the forward scanning direction). It is a technique to do. Hereinafter, such a stacking method to which the present invention is applied is referred to as a reverse scan stacking method.

  FIG. 13 is a diagram for explaining an example of an operation corresponding to such a reverse scan stacking method.

  In the example of FIG. 13, the forward direction of the image forming unit 13-1 is set to the first direction from right to left, while the forward direction of the image forming unit 13-2 is set from left to right. The second direction is set.

  Thereby, the second problem described above is solved. That is, the degree of occurrence of the double image state is reduced as compared with the conventional case.

  That is, the time zone in which the scan position of the image forming unit 13-1 or the image forming unit 13-2 enters the left one-dot chain line region is a time zone near each of the times t10 to t16. Of these times, t10, t12, and t14 are also frame switching timings, so in these neighboring time zones, an image (the left part) of two different frames before and after switching is projected onto the left one-dot chain line area. Will be. However, at other times near the times t11, t13, and t15, an image in which the same frames are simply overlapped, that is, the frames themselves (the left portion thereof) is projected on the left one-dot chain line region. Therefore, since each time interval from time t10 to t16 is expressed in terms of frequency, it is 120 [Hz]. Therefore, for each 120 [Hz], an image (the left part) is as if two different frames before and after switching were combined. Then, the images (the left part thereof) in which the same frames are simply overlapped are sequentially projected onto the left alternate long and short dash line region. As a result, compared with the double image state generated in the right solid line region in the example of FIG.

  Similarly, a time zone in which the scan position of the image forming unit 13-1 or the image forming unit 13-2 enters the right solid line region is a time zone near each of the times t10 to t16. Of these times, t10, t12, and t14 are also frame switching timings, so in these neighboring time zones, an image (right part) of two different frames before and after switching is projected onto the right solid line area. End up. However, at other times near times t11, t13, and t15, an image in which the same frames are simply overlapped, that is, the frames themselves (right side portions thereof) is projected onto the right solid line region. Therefore, every 120 [Hz], an image in which two different frames before and after switching are synthesized (the right side portion) and an image in which the same frame is simply overlapped (the right side portion) are sequentially switched to the right solid line region. It will be projected. As a result, compared with the double image state generated in the right solid line region in the example of FIG. That is, the second problem is solved.

  In addition, the time zones where the respective scan positions of the image forming unit 13-1 and the image forming unit 13-2 enter the central dotted line region are all the time zones near the time between the time t11 and the time t16. . That is, when the time interval of these time zones is expressed by frequency, it becomes 120 [Hz] as shown in FIG. Accordingly, during the period from time t10 to time t12, the central portion of the first frame 81-1 is sequentially projected onto the central dotted line area as if it were 120 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly. Similarly, during the period from time t12 to time t14, the central portion of the second frame 81-2 is successively projected onto the central dotted line area at intervals of 120 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly. Then, during the time t14 to t16, the central portion of the third frame 81-3 is sequentially projected onto the central dotted line area as if it were continuous at an interval of 120 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly.

  In this way, by applying the reverse scan stacking method of the present invention, the degree of occurrence of a double image state between the left one-dot chain line region and the right solid line region while maintaining the state of the central dotted line region (without deterioration) Can be more relaxed than that of the conventional right solid line region. That is, the second problem can be solved.

  As described above, the reverse scan tiling method of the present invention and the reverse scan stacking method of the present invention have been individually described. Of course, these two methods can be easily combined. In this case, the first problem can be solved and the second problem can be solved.

  Specifically, for example, the partial image 51-K of FIG. 9 described above is formed by one image forming unit 13-K in the example of FIG. On the other hand, when the reverse scan tiling method and the reverse scan stacking method are combined, the two image forming units 13 to which the reverse scan stacking method is applied may form the partial image 51-K.

  That is, in this case, the six image forming units 13-1 to 13-6 are mounted on the image generating unit 1. In order to apply the reverse scan tiling method of the present invention, as described above, the image forming unit 13-1 that forms the partial image 51-1 has a first forward direction from right to left. For the image forming unit 13-2 that is set in the direction and forms the partial image 51-2, the forward direction is set to the second direction from the left to the right, and the image that forms the partial image 51-3 About the formation part 13-3, the outward direction is set to the 1st direction. Further, in order to apply the reverse scan stacking method of the present invention, the forward direction of the other image forming unit 13-4 that forms the partial image 51-1 is the second direction (image forming unit 13-1). In the other image forming unit 13-5 that forms the partial image 51-2, the forward direction is the first direction (the direction opposite to the image forming unit 13-2). For the other image forming unit 13-6 that is set and forms the partial image 51-3, the forward direction is set to the second direction (the direction opposite to the image forming unit 13-3).

  By the way, the present inventor further invented the following other first and second methods other than the reverse scan stacking method as a method for solving the second problem. Therefore, hereinafter, the first other method and the second other method will be described individually.

  As described above, one of the factors causing the second problem is that the scan start timing (timing at which the scanning direction changes from the return direction to the forward direction) of the conventional projector is also the frame switching timing. Therefore, the present inventor has invented the following technique as the first other technique in order to remove one of the generation factors.

  In other words, the first other method invented by the present inventors is a method of changing the frame switching timing to a timing different from the scan start timing. Hereinafter, such a method is referred to as a frame switching timing changing method.

  Hereinafter, the frame switching timing changing method will be further described with reference to FIG. That is, FIG. 14 is a diagram for explaining a frame switching timing changing method.

  In the example of FIG. 14, the projected frame and the time axis are the same as those of the example of FIG. 10 and the example of FIG.

  As shown in the timing chart of the scan position in FIG. 14, the frame switching timing changing method can be realized if only one image forming unit 13 is mounted on the image forming apparatus 1. Of course, the frame switching timing changing method can be realized by setting all the forward directions of two or more image forming units 13 to be the same and using the stacking method together. However, in the following description, it is assumed that only one image forming unit 13 is mounted on the image forming apparatus 1.

  The image projected on the left one-dot chain line region in the time zone when the scan position of the image forming unit 13 enters the left one-dot chain line region is basically the same as the example of FIG. Therefore, a double image state in the left one-dot chain line region does not particularly occur.

  In addition, the frame switching timing is set to times t10, t12, and t14 in the examples of FIGS. 10 and 13, whereas in the example of FIG. 14, 1/240 [s] (240 [ Hz] = 60 [Hz] × 4) Times ta, tc, and te shifted by 4) later. The frame switching timing in the frame switching timing changing method may be any timing as long as it is different from the original frame switching timing. However, in the example of FIG. 14, the timing at which the scan position of the image forming unit 13 is near the center of the frame (the position of the projection surface of the image forming target unit 14 on which it is projected), that is, the times ta, tc, te. However, this is adopted as the frame switching timing.

  Accordingly, the time zone in which the scan position of the image forming unit 13 enters the right solid line region is a time zone near the times t10, t12, t14, and t16, but the frames are not switched in these time zones. Accordingly, in exactly the same manner as the left one-dot chain line region, each frame (the left side portion) is projected sequentially onto the right solid line region at every frame rate of 60 [Hz]. As a result, a double image state does not occur particularly in the right solid line region. That is, the second problem (double image state) occurring in the right solid line region in the example of FIG. 10 is reduced in the degree of occurrence in the example of FIG. 14, that is, the example of applying the frame switching timing change method. Is done.

  In the example of FIG. 14, the times ta, tc, and te, which are frame switching timings, are the times when the scan position of the image forming unit 13 enters near the center, that is, the times when entering the center dotted line region, as described above. ing. Therefore, in a time zone near the times ta, tc, and te, an image composed of the right half of the frame before switching and the left half of the frame after switching is projected as if it were in the center dotted line area. This will be further described with reference to FIG.

  In FIG. 15, the same time axis as that of FIG. 14 (however, a time axis inverted by 90 degrees) is shown at the bottom.

  However, the example of FIG. 14 and the example of FIG. 15 are different from each other in the frames projected on the image forming target portion 14. That is, in the example of FIG. 14, the frame 81-1 is projected as the first frame, the frame 81-2 is projected as the next second frame, and the frame 81-3 is further projected as the next third frame. Was projected. On the other hand, in the example of FIG. 15, the frame 90 (only the left half image 90L is shown in FIG. 15) is projected as the 0th frame before the first frame, and the first frame Frame 91 is projected as a frame, frame 92 is projected as the next second frame, and frame 93 is projected as the next third frame.

  In the example of FIG. 15, unlike the example of FIG. 14, the forward direction of the image forming unit 13 (the forward scanning direction) is a direction from left to right. This is to facilitate understanding of FIG. 15 by matching the direction of the time axis.

  At the top of FIG. 15, an image (hereinafter referred to as an original image) projected onto the image forming target portion 14 by one-side scanning is schematically shown. The pulse train below these original images indicates a video synchronization signal FRMsync having a normal frequency (60 [Hz]).

  In the center of FIG. 15, an image (hereinafter referred to as a normal image) projected onto the image forming target portion 14 by the reciprocating scan when the frame switching timing and the scan start timing coincide is schematically shown. It is shown. The pulse train below these normal images indicates a video synchronization signal FRMsync having a double frequency (120 [Hz]).

  At the bottom of FIG. 15, as a result of applying the frame switching timing change method, the frame switching timing is shifted by the same time (1/240 [s]) as the example of FIG. 14 with respect to the scan start timing. In this case, an image (hereinafter referred to as a phase conversion image) projected onto the image formation target portion 14 by reciprocal scanning is schematically shown. The pulse train below these phase-converted images indicates a video synchronization signal FRMsync having a double frequency (120 [Hz]).

  When the original image is projected on the image forming target portion 14, the frame 91 is projected only once by the scanning in the forward direction of the image forming portion 13 between times t10 and t12 (scanning in the backward direction is prohibited). During the time t12 to t14, the frame 92 is projected only once by scanning in the forward direction of the image forming unit 13 (scanning in the backward direction is prohibited).

  Further, when a normal image is projected on the image forming target unit 14, the frame 91 is projected once by scanning in the forward direction of the image forming unit 13 between times t10 and t11, and between times t11 and t12. In the meantime, the frame 91 is projected once more by scanning in the backward direction of the image forming unit 13. Next, during time t12 to t13, the frame 92 is projected once by scanning in the forward direction of the image forming unit 13, and during time t13 to t14, the frame 92 is scanned by scanning in the backward direction of the image forming unit 13. It is projected once more. After time t14, the frame 93 is projected once by scanning in the forward direction of the image forming unit 13, and then, although not shown, the frame 93 is projected once more by scanning in the backward direction of the image forming unit 13. .

  On the other hand, when the phase change image is projected on the image forming target portion 14 by applying the frame switching timing changing method, the following images are sequentially projected.

  That is, during time t10 to ta, the left portion 90L of the frame 90 is sequentially projected rightward from the left end line by scanning in the forward direction of the image forming unit 13, and at time ta which is the frame switching timing. Then, the projection target is switched from the frame 90 to the frame 91, and this time, the right portion 91R of the frame 91 is a line near the center of the frame 91 by scanning in the forward direction of the image forming unit 13 between times ta to t11. Projected sequentially from right to left. Accordingly, in the time zone near time ta, an image 94 composed of the left half image 90L of the pre-switching frame 90 and the right half image 91R of the post-switching frame 91 is an image formation target portion 14. It will be projected as if.

  Since there is no frame switching timing between times t11 and t12, the frame 91 is projected once by scanning in the backward direction of the image forming unit 13.

  Hereinafter, similarly, during the time t12 to tc, the left portion 91L of the frame 91 is sequentially projected rightward from the left end line by scanning in the forward direction of the image forming unit 13, and it is the frame switching timing. At time tc, the projection target is switched from the frame 91 to the frame 92, and this time, during the time tc to t13, the right portion 92R of the frame 92 is moved to the center of the frame 92 by scanning in the forward direction of the image forming unit 13. Projected sequentially from nearby lines to the right. Therefore, in the time zone near time tc, an image 95 composed of the left half image 91L of the frame 91 before switching and the right half image 92R of the frame 92 after switching is an image formation target portion 14. It will be projected as if.

  Since there is no frame switching timing between time t13 and time t14, the frame 92 is projected once by scanning in the backward direction of the image forming unit 13.

  During the time t14 to te, the left portion 92L of the frame 92 is sequentially projected rightward from the left end line by the forward scanning of the image forming unit 13, and is projected when the time te is the frame switching timing. Is switched from the frame 92 to the frame 93, and this time, the right portion 93 </ b> R of the frame 93 is sequentially projected rightward from the line near the center of the frame 93 by the forward scanning of the image forming unit 13. Therefore, in the time zone near time te, an image 96 composed of the left half image 92L of the frame 92 before switching and the right half image 93R of the frame 93 after switching is an image formation target portion 14. It will be projected as if.

  Thereafter, although not shown, the frame 93 is projected once by scanning in the backward direction of the image forming unit 13.

  As described above, when the frame switching timing changing method is applied, an area in which the vicinity of the center of each frame of the image forming target portion 14 is projected, that is, the center dotted line referred to in the example of FIG. Focusing on the area, in the time zone near the times ta, tc, and te, which are frame switching timings, the left part of the frame before switching (right part in the example of FIG. 14) and the right part of the frame after switching (FIG. 14). In this example, an image (the center portion) composed of the left portion is projected. However, in other times near the times tb and td, there is no particular frame switching timing, so only the projection target frame (the central portion thereof) is projected. Therefore, every 120 [Hz], an image composed of the left part of the frame before switching (right part in the example of FIG. 14) and the right part of the frame after switching (left part in the example of FIG. 14) The central part) and the projection target frame itself (the central part) are interchanged and sequentially projected. As a result, when compared with the double image state generated in the right solid line region in the example of FIG.

  As described above, the frame switching timing changing method, which is the first other method, has been described as another method for solving the second problem other than the reverse scan stacking method. Next, a second other method will be described.

  As described above, the cause of the second problem (double image state) is that a composite image in which two different frames before and after switching are combined is projected every predetermined period. Also, one of the solutions is to reduce the degree of occurrence by further projecting the projection target frame between the synthesized images. An example of a method adopting this solution is the above-described reverse scan stacking method, and the second other method as described below.

  In other words, the second other method employs a frequency three times the normal (frame rate 60 [Hz]), that is, 180 [Hz] as the frequency of the video synchronization signal FRMsynk, and performs reciprocal scanning. It is a method to adopt. Hereinafter, such a method is referred to as a triple scan method.

  Hereinafter, the triple scanning method will be further described with reference to FIG.

  In the example of FIG. 16, the projected frame and the time axis are the same as those of the example of FIG. 10 and the example of FIG. However, in the example of FIG. 16, it is illustrated from time t10 to t14 on the time axis, and accordingly, only the first frame 81-1 and the second frame 81-2 are illustrated. In the example of FIG. 16, the frame switching timing is set to times t10, t12, and t14 as in the examples of FIG. 10 and FIG.

  As shown in the scan position timing chart of FIG. 16, the triple scan method can be realized if only one image forming unit 13 is mounted on the image forming apparatus 1. Of course, the triple scan method can be realized by setting all the forward directions of two or more image forming units 13 to be the same and using the stacking method together. However, in the following description, it is assumed that only one image forming unit 13 is mounted on the image forming apparatus 1.

  The time zone in which the scan position of the image forming unit 13 enters the left one-dot chain line region is a time zone near the times tA, t12, and tD, and the time that coincides with the frame switching timing is only t12 in these time zones. Therefore, in the time zone near the time t12, that is, in the vicinity of the timing when the projection is switched from the first frame 81-1 to the second frame 81-2, the first frame 81-1 and the second frame A composite image (the left portion thereof) in which two different images such as the frame 81-2 are combined is projected onto the left one-dot chain line region. However, in other time zones near the times tA and tD, an image in which the same frames are simply overlapped, that is, the frames themselves (the left portion thereof) is projected onto the left-hand dashed line region. Moreover, when each time interval of time tA, t12, tD is represented by a frequency, it will be 90 [Hz] as FIG. 16 shows. Therefore, every 90 [Hz], the composite image in which two different frames before and after switching overlap (the left part) and the image in which the same frame simply overlaps (the left part) are swapped in the left one-dot chain line region. It will be projected sequentially. As a result, when compared with the double image state generated in the right solid line region in the example of FIG.

  The time zone in which the scan position of the image forming unit 13 enters the right solid line region is a time zone near the times t10, tB, tc, and t14. In these time zones, the time that coincides with the frame switching timing is t10, Only t14. Therefore, just like the left one-dot chain line region, for every 90 [Hz], a composite image in which two different frames before and after switching overlap (its right part) and an image in which the same frame simply overlaps (its right part). Are sequentially projected onto the right solid line region. As a result, when compared to the double image state that occurred in the right solid line region in the example of FIG. That is, the second problem is solved.

  In addition, any time zone in which the scan position of the image forming unit 13 enters the central dotted line region is a time zone near the time between times t10, tA, tB, t12, tC, tD, and t14. That is, the time interval of these time zones is 180 [Hz] when expressed in frequency. Therefore, during the period from time t10 to time t12, the central portion of the first frame 81-1 is sequentially projected onto the central dotted line area as if it were continuously spaced at an interval of 180 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly. Similarly, during the period from t12 to t14, the central portion of the second frame 81-2 is successively projected onto the central dotted line area at an interval of 180 [Hz]. Accordingly, during this time, the double image state in the central dotted line region does not occur particularly.

  As described above, even when the triple scan method of the present invention is applied, the degree of occurrence of a double image state between the left one-dot chain line region and the right solid line region while maintaining the state of the central dotted line region (without deteriorating). Can be more relaxed than that of the conventional right solid line region. That is, the second problem can be solved.

  As described above, the reverse scan stacking method, the frame switching timing method, and the triple scan method have been described as methods for solving the second problem.

  Incidentally, in the above-described example, it is assumed that the image forming unit 13 performs reciprocal scanning. However, as described above, the image forming unit 13 is provided with a one-side mode for performing one-sided scanning as well as a reciprocating mode for performing two-way scanning as the projection mode. Therefore, the image forming unit 13 can easily perform the one-sided scan only by changing the projection mode to the one-side mode. That is, if two or more image forming units 13 are mounted on the image processing apparatus 1, it is possible to easily realize a tiling method based on one-side scanning.

  Hereinafter, a tiling method based on one-side scanning will be described with reference to FIGS. 17 and 18.

  FIGS. 17 and 18 are diagrams corresponding to FIGS. 8 and 9 for the reciprocating scan, respectively. That is, also in the examples of FIGS. 17 and 18, the image forming apparatus 1 is assumed to be equipped with three image forming units 13-1 to 13-3.

  In the example of FIG. 17, the forward directions of the image forming units 13-1 to 13-3 are all set to the same direction, that is, the direction from right to left.

  In the one-side scan, each of the image forming units 13-1 to 13-3 performs only the scan in the forward direction (the direction from right to left), and does not perform the scan in the backward direction (the direction from left to right) ( Ban). Accordingly, when focusing on the blending area 61, at times tα, tβ, and tγ when the scanning direction is reversed from the forward direction to the backward direction, the image forming unit 13-2 that forms the partial image 51-2 scans the left by The second blended image is projected as a blending area 61 in which the gray density increases in the direction from right to right (the leftmost is the lightest and the rightmost is the darkest). In contrast, at times (scan start timings) t1, t3, t5, and t7 when the scanning direction is reversed from the backward direction to the forward direction, scanning of the outward path of the image forming unit 13-1 that forms the partial image 51-1. Thus, the first blending image in which the gray density decreases from left to right (the leftmost side is the darkest and the rightmost side is the lightest) is projected as the blending region 61. The same applies to the blending area 62.

  Therefore, the first problem may occur depending on the time interval between time tα and time t3, the time interval between time tβ and time t5, and the time interval between time tγ and time t7, that is, a blending region. There is a possibility that flickers 61 and 62 occur.

  Even in such a case, the above-described reverse scan tiling method is effective. That is, the first problem can be solved by applying the reverse scan tiling method. FIG. 18 is a diagram for explaining such a reverse scan tiling method based on one-sided scanning.

  That is, in the example of FIG. 18, as in the example of FIG. 9, the forward direction of the image forming unit 13-1 that forms the partial image 51-1 including the blending region 61 as the right side portion is from right to left. On the other hand, for the image forming unit 13-2 that forms the partial image 51-2 including the blending region 61 as the left side portion, the forward direction is set to the second direction from left to right. The Similarly, for the image forming unit 13-2 that forms the partial image 51-2 including the blending region 62 as the right side portion, the forward direction is set to the second direction as described above. As for the image forming unit 13-3 that forms the partial image 51-3 including the left side portion, the forward direction is set to the first direction.

  Thereby, the first problem described above does not occur.

  That is, in the time zone near the time tα, tβ, tγ when the scanning direction is reversed from the forward direction to the backward direction, the scan position of the image forming unit 13-1 is not within the formation position of the blending region 61, and The scan position of the image forming unit 13-2 is not included in the blending area 61 formation position. Therefore, nothing (except afterimage) is projected as the blending region 61 in the time zone near the times tα, tβ, and tγ.

  Further, in a time zone near the time when the scanning direction is reversed from the backward direction to the forward direction (scan start timing) t1, t3, t5, t7, the partial image 51 projected by the forward scanning of the image forming unit 13-1. −1 and the second blended image that is the left side portion of the partial image 51-2 projected by the image forming unit 13-2 are combined, and as a result, the same density is obtained. The image of one gray surface (having the same luminance value R as the other areas of the entire image 71) is projected as the blending area 61.

  Therefore, as the blending area 61, images of a gray surface having the same density, that is, the same image are sequentially projected at a period of 60 [Hz]. In other words, if the projection time (scan time) of the blending area 61 is sufficiently short, it is equivalent to sequentially projecting the same image at a frame rate of 60 [Hz], and tiling in the blending area 61 is performed. Flicker due to the occurrence of this is less likely to occur. That is, the first problem does not occur (is solved). Although not shown and described, this is exactly the same for the blending area 62.

  As described above, the methods for solving the above-described first and second problems of the prior art, that is, the methods of the present invention include the reverse scan tiling method, the reverse scan stacking method, the frame switching timing change method, and the triple Explained various methods such as scanning methods.

  As described above, the reverse scan tiling method and the reverse scan stacking method can be combined. However, if other combinations are possible, two or more of the various methods of the present invention can be selected and combined as appropriate.

  Further, the application destination of these various methods of the present invention is not particularly limited to the image forming apparatus 1 of FIG. For example, a conventional projector manufactured by fixing the forward direction (the forward scanning direction) in the first direction (for example, the left direction to the right direction), and the forward direction is the second direction (for example, the right direction to the left direction). The present invention is also applicable to an image forming apparatus in which only a necessary number of projectors manufactured in a fixed manner are prepared and mounted in place of the image forming units 13-1 to 13-N. Various methods can be applied.

  Alternatively, the various methods of the present invention can also be applied to a printer or the like equipped with image forming units 13-1 to 13-N that form images on a paper medium or the like instead of the image forming target unit 14. it can. In addition, in the above-described example, the image forming apparatus 1 in FIG. 1 that generates a two-dimensional image by scanning a vertical one-dimensional image in the horizontal direction is employed. However, a block image (horizontal / vertical primary) including one or more pixels is employed. Various methods of the present invention can also be applied to an image forming apparatus that generates a one-dimensional or higher image by scanning an original image) in a predetermined scanning direction. In other words, after all, the various technique destinations of the present invention scan a light beam corresponding to a block image composed of one or more pixels, thereby forming a one-dimensional or higher image on a predetermined image forming target (screen or the like). A forming device is sufficient.

  In addition, the image forming apparatus 1 in FIG. 1 can be configured by storing the components such as the image signal output unit 11 to the image forming unit 13 in one casing, or each component can be stored in a separate casing. It can also be accommodated. In other words, in this specification, if the entire apparatus including a plurality of apparatuses and a plurality of processing units is referred to as a system, the image forming apparatus 1 can be regarded as the image forming system 1.

  By the way, the above-described series of processing (processing corresponding to various methods of the present invention) can be executed by hardware, or can be executed by software.

  When the above-described series of processing is executed by software, various functions can be realized by installing a program that constitutes the software in a dedicated hardware or by installing various programs. For example, a general-purpose personal computer that can be executed is installed from a network or a recording medium.

  For example, in the image forming unit 13 of FIG. 2, the recording medium including such a program is a package medium distributed to provide a program to the user, that is, a magnetic medium on which the program is recorded. Disk (including floppy disk), optical disk (including compact disk-read only memory (CD-ROM), DVD (digital versatile disk)), magneto-optical disk (including MD (mini-disk)), or semiconductor memory In addition to a removable recording medium (package medium) (not shown), a central control unit 21 in which a program is provided, which is provided to the user in a state of being incorporated in the apparatus main body in advance, or not shown. It consists of a hard disk.

1 is a block diagram illustrating a configuration example of an image forming apparatus to which the present invention is applied. FIG. 2 is a block diagram illustrating a detailed configuration example of an image forming unit in FIG. 1. It is a figure which shows the example of the projection surface of the to-be-image-formed object part of FIG. FIG. 5 is a diagram for explaining a scanning operation of a scanner of the image forming unit in FIG. 2. FIG. 5 is a diagram illustrating an example of an image formed on the projection surface of the image forming target unit in FIG. 3 as a result of the scanning operation in FIG. 4 performed by the scanner of the image forming unit in FIG. 2. FIG. 6 is a diagram for explaining reciprocal scanning when the forward direction is from left to right in the scanning operation of the image forming unit in FIG. 2. FIG. 5 is a diagram for explaining reciprocal scanning when the forward direction is from right to left in the scanning operation of the image forming unit in FIG. 2. It is a figure for demonstrating the conventional tiling method by a reciprocating scan. It is a figure for demonstrating the reverse scan tiling method by the reciprocating scan to which this invention is applied. It is a figure explaining the conventional problem which generate | occur | produces when a moving image is formed in the projection surface of the to-be-image-formed object part by the conventional reciprocating scan. It is a figure explaining the conventional problem which generate | occur | produces when a moving image is formed in the projection surface of the to-be-image-formed object part by the conventional reciprocating scan. It is a figure explaining the conventional problem which generate | occur | produces when a moving image is formed in the projection surface of the to-be-image-formed object part by the conventional reciprocating scan. It is a figure for demonstrating the reverse scan stacking method to which this invention is applied. It is a figure for demonstrating the frame switching timing change method to which this invention is applied. It is a figure for demonstrating the frame switching timing change method to which this invention is applied. It is a figure for demonstrating the 3 times scanning method to which this invention is applied. It is a figure for demonstrating the conventional tiling method by the one-sided scan. It is a figure for demonstrating the reverse scan tiling method by the one side scan to which this invention is applied.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Image forming apparatus, 11-1 thru | or 11-N Image signal output part, 12 Blending processing part, 13, 13-1 thru | or 13-N Image forming part, 14 Image formation object part, 21 Central control part, 22 Image processing Unit, 23 drive timing control unit, 24 GLV module, 25 projection optical system, 26 scanner, 26a scan mirror, 27 scanner control unit, 28 operation unit, 51-1 to 51-3 partial image, 61, 62 blending area, 71 Whole image

Claims (8)

By superimposing a predetermined part of the first partial image and a predetermined part of the second partial image, an image composed of the first partial image and the second partial image is set as an image formation target. In the image forming apparatus to be formed,
First, the light corresponding to each of the plurality of block images constituting the first partial image is scanned in the first direction and irradiated to the image formation target, respectively. A partial image is formed on the object to be imaged, and then scanned in a second direction opposite to the first direction to irradiate the object to be imaged, respectively. First image forming means for repeatedly executing a process of forming a partial image on the image forming target;
The image formation is performed by first scanning light corresponding to each of a plurality of block images constituting the second partial image in the second direction substantially in synchronization with the first image forming means. By irradiating each of the objects, the second partial image is formed on the object to be imaged, and then scanned in the first direction to irradiate each object to be imaged. An image forming apparatus comprising: a second image forming unit that repeatedly executes a process of forming the second partial image on the image forming target. The image formation is performed by first scanning light corresponding to each of a plurality of block images constituting the first partial image in the second direction substantially in synchronization with the first image forming means. By irradiating each of the objects, the first partial image is formed on the object to be imaged, and then scanned in the first direction to irradiate each object to be imaged. A third image forming unit that repeatedly executes a process of forming the first partial image on the image forming target;
The image formation is performed by first scanning light corresponding to each of a plurality of block images constituting the second partial image in the first direction substantially in synchronization with the first image forming means. By irradiating each of the objects, the second partial image is formed on the object to be imaged, and then scanned in the second direction to irradiate each object to be imaged. The image forming apparatus according to claim 1, further comprising: a fourth image forming unit that repeatedly executes a process of forming the second partial image on the image forming target. By superimposing a predetermined part of the first partial image and a predetermined part of the second partial image, an image composed of the first partial image and the second partial image is set as an image formation target. In the image forming method of the image forming apparatus to be formed,
First, the light corresponding to each of the plurality of block images constituting the first partial image is scanned in the first direction and irradiated to the image formation target, respectively. A partial image is formed on the object to be imaged, and then scanned in a second direction opposite to the first direction to irradiate the object to be imaged, respectively. A first image forming step of repeatedly executing a process of forming a partial image on the image forming target;
The light corresponding to each of the plurality of block images constituting the second partial image is first scanned in the second direction substantially in synchronization with the processing of the first image forming step. By irradiating each image forming target, the second partial image is formed on the image forming target, and then scanned in the first direction to irradiate each image forming target. And a second image forming step of repeatedly executing a process of forming the second partial image on the image forming target. The light corresponding to each of the plurality of block images constituting the first partial image is first scanned in the second direction substantially in synchronization with the processing of the first image forming step. By irradiating each image forming object, the first partial image is formed on the image forming object, and then scanned in the first direction to irradiate each image forming object. Thus, a third image forming step of repeatedly executing the process of forming the first partial image on the image forming target;
Substantially in synchronization with the processing of the first image forming step, the light corresponding to each of the plurality of block images constituting the second partial image is first scanned in the first direction to scan the object. By irradiating each image forming object, the second partial image is formed on the image forming object, and then scanned in the second direction to irradiate each image forming object. The image forming method according to claim 3, further comprising: a fourth image forming step of repeatedly executing a process of forming the second partial image on the image forming target. In an image forming apparatus for forming an image on an image forming target,
First, the light corresponding to each of the plurality of block images constituting the image is scanned in the first direction to irradiate the object to be imaged, so that the image is to be imaged. And forming the image on the image forming target by scanning in a second direction opposite to the first direction and irradiating the image forming target respectively. First image forming means for repeatedly executing
The light corresponding to each of a plurality of block images constituting the same image is first scanned in the second direction in synchronization with the first image forming means to be the image formation target. By irradiating each of the images, the image is formed on the object to be imaged, and thereafter, scanning the image in the first direction to irradiate each of the objects to be imaged, thereby causing the image to be imaged. An image forming apparatus comprising: a second image forming unit that repeatedly executes a process to be formed on an image forming target. In an image forming method of an image forming apparatus for forming an image on an image forming target,
First, the light corresponding to each of the plurality of block images constituting the image is scanned in the first direction to irradiate the object to be imaged, so that the image is to be imaged. And forming the image on the image forming target by scanning in a second direction opposite to the first direction and irradiating the image forming target respectively. A first image forming step of repeatedly executing
Substantially in synchronization with the processing of the first image forming step, the light corresponding to each of a plurality of block images constituting the same image is first scanned in the second direction to form the imaged object. By irradiating each of the objects, the image is formed on the object to be imaged, and after that, by scanning in the first direction and irradiating each of the objects to be imaged, the image is formed. And a second image forming step of repeatedly executing the process of forming the image forming target. By superimposing a predetermined part of the first partial image and a predetermined part of the second partial image, an image composed of the first partial image and the second partial image is set as an image formation target. In the image forming apparatus to be formed,
First, the light corresponding to each of the plurality of block images constituting the first partial image is scanned in the first direction from the first start position to irradiate the image formation target respectively. A first image forming unit that repeatedly executes a process of forming the first partial image on the image forming target and then returning a scanning position to the first start position;
The light corresponding to each of the plurality of block images constituting the second partial image is first synchronized with the first image forming means from the second start position to the first direction. The second partial image is formed on the image forming target by scanning in the second direction opposite to the target and irradiating the image forming target, and then the scan position is set to the second target. An image forming apparatus comprising: a second image forming unit that repeatedly executes a process of returning to a start position. By superimposing a predetermined part of the first partial image and a predetermined part of the second partial image, an image composed of the first partial image and the second partial image is set as an image formation target. In the image forming method of the image forming apparatus to be formed,
First, the light corresponding to each of the plurality of block images constituting the first partial image is scanned in the first direction from the first start position to irradiate the image formation target respectively. A first image forming step of repeatedly executing the process of forming the first partial image on the image forming target and then returning the scanning position to the first start position;
The light corresponding to each of the plurality of block images constituting the second partial image is first synchronized with the processing in the first image forming step from the second start position to the first direction. The second partial image is formed on the image forming target by scanning in the second direction opposite to the direction and irradiating the image forming target, and then the scanning position is set to the first position. And a second image forming step of repeatedly executing the process of returning to the start position of 2. An image forming method comprising:

Images