JP4706300B2 - Projector and projector control method - Google Patents

Description

  The present invention relates to a projector and a projector control method.

Conventionally, a light modulation element that modulates a light beam emitted from a light source according to image information to form an optical image, and a projection lens that enlarges and projects the optical image formed by the light modulation element on a screen are provided. Projectors are known.
In such a projector, the relative positions of a plurality of lenses constituting the projection lens are changed so that an optical image is formed on the screen (the position of the focus lens that contributes to the focus adjustment (the focus lens among the plurality of lenses)). It is necessary to perform focus adjustment by moving the position) in the optical axis direction with respect to other lenses. Conventionally, a projector that performs such focus adjustment has been proposed (see, for example, Patent Document 1).
In the projector described in Patent Document 1, electric focus adjustment (manual adjustment control) for detecting a press of an electric focus fur switch or an electric focus near switch by a user and changing a focus position for a time during which the pressed state continues, It is possible to carry out autofocus adjustment (automatic adjustment control) that detects when the autofocus switch is pressed by the user and changes the focus position to the in-focus position where the projected image on the screen is in focus. Has been.

Further, in the projector as described above, in order to change the contour (size) of the projected image on the screen, the relative positions of the plurality of lenses constituting the projection lens are changed (zoom adjustment among the plurality of lenses). It is necessary to perform zoom adjustment by moving the position of the zoom lens that contributes to (zoom position) in the optical axis direction with respect to the other lenses. Conventionally, a projector that performs such zoom adjustment has been proposed (see, for example, Patent Document 2).
In the projector described in Patent Document 2, when performing the focus adjustment and the zoom adjustment, the focal length of the projection lens is changed by changing the outline of the projection image. , Focus adjustment is carried out.

JP-A-9-130712 Japanese Patent Laid-Open No. 8-292396

By the way, in the focus adjustment as described above, a focus position change range in which the focus position can be changed mechanically (hereinafter, referred to as a mechanical limit range) is generally a focus adjustment margin or a manufacturing error of a projection lens. In consideration of the above, it is set to be wider than the design range defined by the specifications of the projection lens.
When the machine limit range is set as described above, the focus position of the manual adjustment control and the focus adjustment control of the automatic adjustment control is changed including the widely set range as described above. There is a problem that it takes more time.

  Here, in order to solve the above problem, the focus position change range in the focus adjustment control is set to a design range defined by the specification of the projection lens, for example. That is, the focus position change range in the focus adjustment control is set to be narrower than the machine limit range. With such a configuration, in the focus adjustment control, the focus position is changed within the range set narrower than the mechanical limit range as described above, so that the focus adjustment can be performed in a shorter time. However, in the case of a configuration in which zoom adjustment is possible, such as the projector described in Patent Document 2, since the focal length of the projection lens is changed according to zoom adjustment, the focus position change range in the focus adjustment control is changed. When preset as described above, the focus position may be changed to a focus position where the projected image is not in focus at a predetermined zoom position, and focus adjustment control is performed within the effective focus position change range. Cannot be implemented.

  An object of the present invention is to provide a projector that can shorten the focus adjustment time by the focus adjustment control and can perform the focus adjustment control in an effective focus position change range, and a projector control method.

The projector of the present invention is a projector including a light modulation element that modulates a light beam emitted from a light source according to image information to form an optical image, and a projection optical device that enlarges and projects the optical image on a screen. The projection optical device includes a projection lens that has a plurality of lenses and enlarges and projects the optical image onto the screen via the plurality of lenses, and performs focus adjustment of the projection image that is enlarged and projected onto the screen. A focus position changing unit that changes a focus position that is a relative position of the plurality of lenses, and a zoom position changing unit that changes a zoom position that is a relative position of the plurality of lenses in order to perform zoom adjustment of the projection image; A focus position detection unit that detects the focus position, a zoom position detection unit that detects the zoom position, and the zoom In the detected zoom position detected by the position detection unit, when the projection distance to the screen is the shortest projection distance defined by the specification of the projection lens, the shortest focus restriction position where the projection image is in focus When the projection distance is the longest projection distance specified by the specifications of the projection lens, a focus position change range is set that allows the focus position to be changed to the longest focus limit position where the projection image is in focus. A change range setting unit, a setting input unit for setting and inputting focus adjustment information for performing the focus adjustment, and focus adjustment for driving the focus position changing unit based on the focus adjustment information to change the focus position A focus adjustment control unit that performs control, and the focus adjustment control unit Carcass position detected detected focus position by the detector, and on the basis of the focus position changing range, which comprises carrying out the focus adjustment control in the focus position changing range.
Here, the focus position, which is the relative position of the plurality of lenses, means the relative position between the focus lens that contributes to the focus adjustment and the other lenses among the plurality of lenses.
The zoom position, which is the relative position of the plurality of lenses, means the relative position between the zoom lens that contributes to zoom adjustment and the other lenses among the plurality of lenses.

In the present invention, for example, the conventional mechanical limit range in which the focus position can be changed mechanically is adjusted with the shortest projection distance defined by the specifications of the projection lens in consideration of the manufacturing error of the projection lens. It is set so as to be wider than the range from the shortest focus limit position on the design that is in focus to the longest focus limit position on design that is in focus at the longest projection distance. The change range setting unit then aligns the projection image at the longest projection distance from the shortest focus limit position where the projection image is in focus at the shortest projection distance at the current detected zoom position detected by the zoom position detection unit. The range up to the longest focus limit position that is in focus is set as the focus position change range. For this reason, the focus position change range can be set to a range narrower than the machine limit range. Then, the focus adjustment control unit recognizes the detected focus position detected by the focus position detection unit and changes the focus position within the focus position change range that is narrower than the machine limit range, thereby performing focus adjustment control. As a result, the focus adjustment time in the focus adjustment control can be shortened.
In addition, every time the zoom position is changed by zoom adjustment, the change range setting unit sets a focus position change range according to the changed zoom position, so that the projected image is in a focused state at the changed zoom position. Focus adjustment control can always be performed within an effective focus position change range without changing the focus position to a focus position that does not occur.

  In the projector according to the aspect of the invention, when the projection image has a wide end zoom position where the projected image is the maximum, and the zoom position is the wide end zoom position, the projection image is in focus at the shortest projection distance. Wide end position information associated with a focus position, and a wide end longest focus position at which the projection image is in focus at the longest projection distance, a tele end zoom position at which the projection image is a minimum contour, and the zoom position Is the tele-end zoom position, the shortest tele-end focus position at which the projection image is in focus at the shortest projection distance, and the longest tele-end focus position at which the projection image is in focus at the longest projection distance. A tele-end position information associated with the position information storage unit, and the change range setting unit includes the wide-end position information and An apportioning information generating unit that generates apportioning information obtained by apportioning the wide-end zoom position based on the tele-end position information and the tele-end zoom position at the detected zoom position; and, based on the apportioning information, the wide-end position information And the shortest focus limit position between the wide end shortest focus position and the tele end shortest focus position based on the tele end position information, the wide end longest focus position based on the wide end position information and the tele end position information, and It is preferable that a focus limit position determination unit that determines the longest focus limit position between the tele end longest focus positions is provided.

  In the present invention, the position information storage unit stores the wide end position information and the tele end position information, and the change range setting unit is based on the wide end position information and the tele end position information. The shortest focus limit position and the longest focus limit position are determined based on the four focus positions of the tele end shortest focus position and the tele end longest focus position. Therefore, for example, each shortest focus limit position and each longest focus limit position corresponding to each zoom position are stored in the storage unit, and the change range setting unit stores the shortest focus limit position and longest focus limit position corresponding to the detected zoom position. The amount of information stored in the storage unit can be effectively reduced as compared with the configuration in which the focus position change range is set by reading out from the storage unit.

In the present invention, the shortest focus limit position and the longest focus limit position can be determined as shown below, for example.
The apportionment information generation unit constituting the change range setting unit generates apportionment information regarding the ratio between the wide end zoom position and the detection zoom position and the tele end zoom position and the detection zoom position.
Then, the focus limit position determination unit constituting the change range setting unit determines the shortest focus limit position by apportioning between the wide end shortest focus position and the tele end shortest focus position according to the ratio, and further, the ratio Accordingly, the longest focus limit position is determined by apportioning between the wide end longest focus position and the tele end longest focus position.
Therefore, the determination of the shortest focus limit position and the longest focus limit position can be easily performed with a simple configuration using the wide end position information and the tele end position information, which are small amounts of information.

  In the projector according to the aspect of the invention, when the zoom position is the tele end zoom position and the projection distance is a predetermined distance, the first focus position where the projected image is in focus and the zoom position is the wide end zoom. At least one of the second focus positions at which the projection image is in focus when the projection distance is the predetermined distance, the tele-end shortest focus position, and the tele-end A difference information storage unit that stores difference information regarding each difference between the longest focus position, the wide end shortest focus position, and the wide end longest focus position; and focus position information acquisition that acquires focus position information regarding the predetermined distance focus position Based on the focus position information and the difference information The tele end shortest focus position, the tele end longest focus position, the wide end shortest focus position, and the wide end longest focus position are calculated, and the tele end position information and the wide end position information based on the calculated focus positions are calculated. It is preferable that a focus position calculation unit stored in the position information storage unit is provided.

Here, the following configuration can be adopted as the difference information.
For example, each difference between the first focus position and the tele end shortest focus position, the tele end longest focus position, the wide end shortest focus position, and the wide end longest focus position, or the second focus position and the tele end shortest focus position. , There is first difference information regarding each difference between the tele end longest focus position, the wide end shortest focus position, and the wide end longest focus position.
Further, for example, each difference between the first focus position and the tele end shortest focus position and the tele end longest focus position, and each second difference between the second focus position and the wide end shortest focus position and the wide end longest focus position. There is difference information.

According to the present invention, since the projector includes the difference information storage unit, the focus position acquisition unit, and the focus position calculation unit, the tele end position information and the wide end position information are stored in the position information storage unit as described below. It can be memorized.
When the difference information storage unit stores the first difference information described above, the focus position information acquisition unit acquires the first focus position or the second focus position. The focus position calculation unit adds each difference based on the first difference information to the first focus position or the second focus position, so that the tele end shortest focus position, the tele end longest focus position, and the wide end shortest focus position. , And the wide end longest focus position are calculated. The focus position calculation unit stores the tele end position information and the wide end position information based on the calculated focus positions in the position information storage unit.
When the difference information storage unit stores the second difference information described above, the focus position information acquisition unit acquires the first focus position and the second focus position. The focus position calculation unit calculates the tele end shortest focus position and the tele end longest focus position by adding each difference based on the second difference information to the first focus position, and sets the second focus position to the second focus position. The wide end shortest focus position and the wide end longest focus position are calculated by adding each difference based on the difference information. The focus position calculation unit stores the tele end position information and the wide end position information based on the calculated focus positions in the position information storage unit.

  As described above, the projector itself calculates the tele-end shortest focus position, the tele-end longest focus position, the wide-end shortest focus position, and the wide-end longest focus position according to the predetermined distance focus position. Based on the tele end position information and the wide end position information, the position information storage unit stores the information. For this reason, for example, when the projector is manufactured, the operator can actually measure or calculate the tele end shortest focus position, the tele end longest focus position, the wide end shortest focus position, and the wide end longest focus position by calculation. Compared with the configuration in which the tele end position information and the wide end position information based on each focus position are stored in the position information storage unit of the projector, the projector is not required to perform complicated operations when the projector is manufactured. Can be easily implemented, and convenience can be improved.

  In the projector according to the aspect of the invention, it is possible to determine the focus position at which the projection image is in a focused state when the zoom position is positioned at a predetermined zoom position and the projection distance is a predetermined distance. A characteristic information storage unit that stores characteristic information related to optical characteristics defined in the specification, and a projection distance information storage unit that stores projection distance information related to the longest projection distance and the shortest projection distance, and the change range setting unit A correspondence characteristic information generating unit that generates correspondence characteristic information indicating a relationship between the projection distance at the detected zoom position and the focus position based on the characteristic information, and based on the correspondence characteristic information and the projection distance information. And a focus limit position determination unit that determines the shortest focus limit position and the longest focus limit position. It is preferable.

In the present invention, the shortest focus limit position and the longest focus limit position can be determined as shown below, for example.
The corresponding characteristic information generation unit constituting the change range setting unit performs zooming based on characteristic information stored in the characteristic information storage unit (for example, information indicating a relationship between the projection distance and the focus position at a predetermined zoom position). Corresponding characteristic information indicating the relationship between the projection distance at the current zoom position detected by the position detection unit and the focus position is generated.
Then, the focus limit position determination unit constituting the change range setting unit, based on the correspondence distance information and the projection distance information stored in the projection distance information storage unit, the focus position at the shortest projection distance (shortest focus limit position) and A focus position at the longest projection distance (longest focus limit position) is determined.
For this reason, when the projector is manufactured, the operator actually measures the information on the shortest focus position at the tele end, the longest focus position at the tele end, the shortest focus position at the wide end, the longest focus position at the wide end, and the difference information. It is not necessary to store these information in the storage unit by calculating or calculating, and it is sufficient to store only the characteristic information and the projection distance information defined in the specifications of the projection lens in the storage unit. In some cases, the projector can be easily manufactured without requiring the operator to perform complicated operations, and convenience can be improved.

In the projector according to the aspect of the invention, the focus adjustment information may be manual adjustment information indicating that the focus position is changed by a predetermined amount, or a relative position of the plurality of lenses may be changed to a focus position at which the projected image is in focus. Automatic adjustment information indicating that the focus adjustment control unit drives the focus position changing unit based on the manual adjustment information to change the focus position by a predetermined amount, and the automatic adjustment information. When performing the manual adjustment control and the automatic adjustment control, the automatic adjustment control for driving the focus position changing unit to change the focus position until the projected image is in an in-focus state based on the Based on the detected focus position detected by the focus position detection unit and the focus position change range, the focus position is changed. It is preferable to change the focus position in the Kas position change range.
In the present invention, the focus position is changed within the focus position change range in both manual adjustment control and automatic adjustment control. For this reason, when the focus adjustment control unit performs manual adjustment control by setting input from the setting input unit by the user, the focus position is not changed to a focus position at which the projected image is not in focus. The user is not allowed to perform useless input operations. In addition, when the focus adjustment control unit performs the automatic adjustment control by the setting input of the setting input unit by the user, the focus position is not changed to the focus position at which the projected image is not in focus. The position can be determined efficiently and quickly. Therefore, it becomes very convenient for the user.

In the projector according to the aspect of the invention, the projection lens may store and hold at least one of the plurality of lenses, and may be configured to rotate about a lens optical axis of the plurality of lenses. The zoom position is configured to include a focus ring and a zoom ring, respectively, and the focus position change unit and the zoom position change unit are configured to rotate the focus ring and the zoom ring, respectively. The position detection unit and the zoom position detection unit are configured to be able to detect the rotation positions of the focus ring and the zoom ring, respectively, and the change range setting unit is configured to detect the shortest focus limit position and the longest position at the detection zoom position. Before corresponding to the focus limit position Each rotation limit position of the focus ring is set as the focus position change range, and the focus adjustment control unit is based on the detected rotation position of the focus ring and the focus position change range detected by the focus position detection unit. The focus adjustment control is preferably performed within the range of each rotation limit position of the focus ring.
In the present invention, the change range setting unit sets the focus position change range at each rotation limit position of the focus ring. Further, the focus adjustment control unit changes the rotation position of the focus ring within the range of the rotation limit positions of the focus ring while recognizing the detected rotation position of the focus ring detected by the focus position detection unit. For this reason, for example, the configuration is simplified compared to a configuration in which a focus position that is a relative position of a plurality of lenses (a position in the optical axis direction of the focus lens that contributes to focus adjustment) is detected and focus adjustment control is performed. And focus adjustment control can be easily performed.

In the projector according to the aspect of the invention, it is preferable that the shortest projection distance and the longest projection distance are set to be different depending on the zoom position.
According to the present invention, since the shortest projection distance (longest projection distance) defined in the specification of the projection lens is set to be different depending on the zoom position, the shortest projection distance (longest projection distance) is set according to the application. It can be set, and the design freedom in the projector can be improved.

The projector control method according to the present invention includes a light modulation element that modulates a light beam emitted from a light source according to image information to form an optical image, a plurality of lenses, and the optical image via the plurality of lenses. A projection lens for enlarging and projecting the image onto the screen, a focus position changing unit for changing a focus position, which is a relative position of the plurality of lenses, to adjust the focus of the projected image that has been enlarged and projected on the screen, and zooming the projection image A projector control method comprising: a projection optical device configured to include a zoom position changing unit that changes a zoom position that is a relative position of the plurality of lenses in order to perform adjustment, and detects the zoom position Zoom position detecting step, and at the detected detected zoom position, a projection distance to the screen is determined by the projection lens. When the projection distance is the longest projection distance defined by the specifications of the projection lens from the shortest focus limit position at which the projection image is in focus when the projection distance is the shortest projection distance defined in the above manner, the projection image A change range setting step for setting a focus position change range that allows the focus position to be changed up to the longest focus limit position where the in-focus state is in focus, and driving the focus position change unit when performing the focus adjustment. And a focus adjustment step for changing the focus position within the focus position change range.
According to the present invention, since the projector control method includes the zoom position detection step, the change range setting step, and the focus adjustment step, the same operations and effects as those of the projector described above can be enjoyed.

[1. First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
[1-1. Projector configuration)
FIG. 1 is a block diagram showing a schematic configuration of a projector 1 in the first embodiment.
The projector 1 modulates a light beam emitted from a light source according to image information to form an optical image, and enlarges and projects the formed optical image on a screen Sc (FIG. 1). As shown in FIG. 1, the projector 1 includes an operation unit 2 as a setting input unit, a power supply unit 3, an image forming unit 4, a rotational position detection unit 5, an imaging unit 6, and a control device 7. It is roughly structured.

  The operation unit 2 includes a remote controller (not shown) and buttons and keys provided in the projector 1. The operation unit 2 recognizes an operation by the user and outputs a predetermined operation signal to the control device 7. As shown in FIG. 1, the operation unit 2 includes a focus adjustment input unit 21, a zoom adjustment input unit 22, and the like. In FIG. 1, other input units such as an input unit for turning on / off the projector 1 in the operation unit 2, an input unit for adjusting the volume, and an input unit for adjusting the image quality of the projected image are illustrated. Is omitted.

The focus adjustment input unit 21 is an input button for causing the control device 7 to perform focus adjustment of the projection image projected on the screen Sc. As illustrated in FIG. 1, the manual adjustment input unit 211 and the automatic adjustment input unit 212.
The manual adjustment input unit 211 is an input button for causing the control device 7 to perform manual adjustment control (to be described later) for manually adjusting the focus adjustment, and includes a fur button 211A and a near button 211B as shown in FIG. The manual adjustment input unit 211 recognizes that the user has pressed the fur button 211A or the near button 211B, and sends a predetermined operation signal as manual adjustment information to the control device 7 only when the user has performed the pressing. Output.
The automatic adjustment input unit 212 is an input button for causing the control device 7 to perform automatic adjustment control (to be described later) for automatically adjusting focus adjustment. Then, the automatic adjustment input unit 212 recognizes the pressing by the user and outputs a predetermined operation signal as automatic adjustment information to the control device 7.

The zoom adjustment input unit 22 is an input button for causing the control device 7 to perform zoom adjustment of the projection image projected on the screen Sc, and as shown in FIG. 1, an area enlargement button 221 and an area reduction button 222.
The area enlargement button 221 and the area reduction button 222 are input buttons for causing the control device 7 to perform zoom adjustment control, which will be described later, for enlarging and reducing the area (size) of the projected image. Then, the zoom adjustment input unit 22 recognizes that the user has pressed the area enlargement button 221 or the area reduction button 222, and sends a predetermined operation signal to the control device 7 only when the user has performed the depression. Output.

  The power supply unit 3 supplies power supplied from the outside to each unit of the projector 1. Although not shown in the figure, the power source unit 3 is in a main power source that supplies power supplied from the outside to each unit of the projector 1 and a state in which the main power source is turned off by the operation of the operation unit 2 by the user (standby state). The sub power source is configured to supply power supplied from the outside only to the control device 7 of the projector 1.

Under the control of the control device 7, the image forming unit 4 forms an optical image and enlarges and projects it on the screen Sc. As shown in FIG. 1, the image forming unit 4 includes a light source device 41, a liquid crystal light valve 42 as a light modulation element, a projection optical device 43, and the like.
The light source device 41 emits a light beam toward the liquid crystal light valve 42 under the control of the control device 7. The light source device 41 includes a light source lamp 411 and a lamp driving unit 412.
The light source lamp 411 is configured by an ultra high pressure mercury lamp. It should be noted that other discharge light source lamps such as a metal halide lamp and a xenon lamp may be employed in addition to the ultra-high pressure mercury lamp. Furthermore, not only the discharge light source lamp, but various self-light emitting elements such as a light emitting diode, an organic EL (Electro Luminescence) element, and a silicon light emitting element may be employed.
The lamp driving unit 412 generates a driving signal according to a predetermined driving frequency under the control of the control device 7 and drives the light source lamp 411.

The liquid crystal light valve 42 is a transmissive liquid crystal panel, changes the arrangement of liquid crystal molecules sealed in a liquid crystal cell (not shown) based on a drive signal from the control device 7, and is emitted from the light source device 41. An optical image corresponding to the image information is emitted to the projection optical device 43 by transmitting or blocking the light beam.
The projection optical device 43 enlarges and projects the optical image emitted from the liquid crystal light valve 42 toward the screen Sc. The projection optical device 43 includes a projection lens 431 and a lens driving unit 432.

FIG. 2 is a diagram schematically showing a main part of the projection lens 431. Specifically, FIG. 2 is a view of the main part of the projection lens 431 viewed from the optical axis direction. Since the configuration of the focus ring 431A and the focus lens 431B and the configuration of the zoom ring 431C and the zoom lens 431D are substantially the same, the same reference numerals are given to the same members in FIG.
The projection lens 431 is configured as a combined lens in which a plurality of lenses are housed in a cylindrical barrel. The projection lens 431 enlarges and projects the optical image emitted from the liquid crystal light valve 42 through the plurality of lenses toward the screen Sc.

The lens barrel is configured by connecting a plurality of members, and supports a plurality of lenses by the plurality of members.
Of the plurality of members constituting the lens barrel, the focus ring 431A supports a focus lens 431B that contributes to focus adjustment of the projection image among the plurality of lenses, as shown in FIG. The focus lens 431B may be configured as a single lens, or may be configured as a lens group having a plurality of lenses. The focus ring 431A is configured to be rotatable with respect to other members around the lens optical axis O of the focus lens 431B, and moves to move the focus lens 431B in the optical axis direction with respect to the other lenses. Thus, the position of the focus lens 431B relative to another lens, which is the relative position of the plurality of lenses (hereinafter, referred to as a focus position) is changed, and the focus adjustment of the projected image is performed. That is, the rotation angle of the focus ring 431A corresponds to the focus position.
Specifically, as shown in FIG. 2, the focus ring 431A is rotated and the predetermined position P is moved in the direction of the arrow A1, so that the projected image can be adjusted to a focused state when the projection distance is short. The focus position moves to the side. On the other hand, by moving the predetermined position P in the direction of the arrow A2, the focus position moves to the far end side where the projection image can be adjusted to the in-focus state when the projection distance is long.

  In the present embodiment, as shown in FIG. 2, the predetermined position P is configured to be movable within a range of R1 (for example, 0 °) to R2 (for example, 90 °). That is, the mechanical limit range R12 in which the focus ring 431A can be mechanically rotated is set to a range of R1 to R2. This mechanical limit range R12 takes into account the manufacturing error of the projection lens 431 and the like, from the design shortest focus limit position where the projected image is in focus at the shortest projection distance specified by the specification of the projection lens 431, and is the longest. It is set to be wider than the range up to the design longest focus limit position where the projected image is in focus at the projection distance.

In addition, among the plurality of members constituting the lens barrel, the zoom ring 431C contributes to zoom adjustment of the projected image among the plurality of lenses, as shown in FIG. 2, similarly to the focus ring 431A described above. The zoom lens 431D is supported. The zoom lens 431D may be configured as a single lens, or may be configured as a lens group having a plurality of lenses, like the focus lens 431B described above. Alternatively, the zoom lens 431D may be configured by a plurality of lens groups, and at least one of the plurality of lens groups may be supported by the zoom ring 431C. The zoom ring 431C is configured to be rotatable with respect to other members around the lens optical axis O of the zoom lens 431D, and rotates to move the zoom lens 431D in the optical axis direction with respect to the other lenses. Thus, the position of the zoom lens 431D relative to another lens, which is the relative position of the plurality of lenses (hereinafter referred to as a zoom position) is changed, and zoom adjustment of the projected image is performed. That is, the rotation angle of the zoom ring 431C corresponds to the zoom position.
Specifically, as shown in FIG. 2, by rotating the zoom ring 431C and moving the predetermined position P in the direction of the arrow A1, the position moves to the tele end side where the contour of the projected image is reduced. On the other hand, by moving the predetermined position P in the arrow A2 direction, the zoom position moves to the wide end side where the contour of the projected image is enlarged.

In the present embodiment, as shown in FIG. 2, the predetermined position P is configured to be movable within a range of R1 (for example, 0 °) to R2 (for example, 90 °). That is, the mechanical limit range R12 in which the zoom ring 431C can be mechanically rotated is set to a range from the tele end zoom position R1 to the wide end zoom position R2 shown in FIG.
In addition, the projection lens 431 according to the present embodiment has a characteristic that the focal length (f) changes when the zoom position is changed by moving the zoom ring 431C with respect to another lens.
Furthermore, the shortest projection distance and the longest projection distance of the projection lens 431 of the present embodiment are set to be the same (for example, the shortest projection distance is 1 m and the longest projection distance is 11 m) even when the zoom position is changed. ing.

The lens driving unit 432 rotates the focus ring 431A and the zoom ring 431C of the projection lens 431 under the control of the control device 7. As shown in FIG. 1, the lens driving unit 432 includes a focus position changing unit 432A and a zoom position changing unit 432B.
The focus position changing unit 432A is constituted by, for example, a pulse motor or the like, and rotates the focus ring 431A to move the focus lens 431B relative to other lenses under the control of the control device 7, thereby changing the focus position. .
Similarly to the focus position changing unit 432A, the zoom position changing unit 432B is configured by, for example, a pulse motor, and rotates the zoom ring 431C under the control of the control device 7 so that the zoom lens 431D is moved with respect to other lenses. To change the zoom position.
Note that the focus ring 431A and the zoom ring 431C may be rotated manually in addition to being driven by the lens driving unit 432.

  Although not shown, the projector 1 includes three liquid crystal light valves 42 corresponding to the three colors RGB. The light source device 41 also includes a color light separation optical system that separates light source light into three colors of light. Further, the projection optical device 43 has a combining optical system that generates an optical image representing a color image by combining three color image lights. As for the configuration of such an optical system, various general projector optical system configurations can be used.

The rotational position detector 5 detects the rotational positions of the focus ring 431A and the zoom ring 431C in the projection lens 431. As shown in FIG. 1, the rotation position detection unit 5 includes a focus position detection unit 51 and a zoom position detection unit 52.
The focus position detection unit 51 includes, for example, a rotary encoder disposed on the motor shaft of the focus position change unit 432A, and detects the rotation position (rotation angle) of the focus ring 431A. Then, the focus position detection unit 51 outputs a signal corresponding to the detected rotation position to the control device 7. Since the rotation angle of the focus ring 431A corresponds to the focus position as described above, the control device 7 recognizes the focus position by detecting the rotation position (rotation angle) of the focus ring 431A by the focus position detection unit 51. It will be.
Similarly to the focus position detection unit 51, the zoom position detection unit 52 includes, for example, a rotary encoder disposed on the motor shaft of the zoom position change unit 432B, and detects the rotation position (rotation angle) of the zoom ring 431C. To do. Then, the zoom position detection unit 52 outputs a signal corresponding to the detected rotation position to the control device 7. As described above, since the rotation angle of the zoom ring 431C corresponds to the zoom position, the control device 7 recognizes the zoom position by detecting the rotation position (rotation angle) of the zoom ring 431C by the zoom position detection unit 52. It will be.

  If the rotational position detector 5 is configured to be able to detect the rotational positions of the focus ring 431A and the zoom ring 431C in the projection lens 431, the rotary encoder described above is the other part than the motor shaft in the lens driver 432. It may also be arranged in a member other than the rotary encoder described above.

  The imaging unit 6 captures a projected image (adjustment pattern image described later) enlarged and projected on the screen Sc under the control of the control device 7. The imaging unit 6 is constituted by, for example, a CCD camera including an area sensor using a CCD (Charge Coupled Device) as an imaging device, and images the adjustment pattern image and controls an electrical signal corresponding to the adjustment pattern image. 7 is output.

The control device 7 includes an arithmetic processing device such as a CPU (Central Processing Unit) and executes a predetermined program to control the power supply unit 3, the image forming unit 4, the rotational position detection unit 5, the imaging unit 6, and the like. . Then, the control device 7 causes the image forming unit 4 to enlarge and project an image corresponding to the image signal input from an external device or the like, and adjusts the focus and zoom of the projected image on the screen Sc according to the operation signal from the operation unit 2. Make adjustments. In the following, the control structure of the focus adjustment and the zoom adjustment of the projected image by the control device 7 will be mainly described, and description and illustration of the other control structures will be omitted.
As shown in FIG. 1, the control device 7 includes a signal input unit 71, a liquid crystal panel drive control unit 72, a frame memory 73, a focus adjustment unit 74, a zoom adjustment unit 75, and a storage unit 76.

The signal input unit 71 inputs image signals and the like output from various external devices, converts them into image signals that can be processed by the liquid crystal panel drive control unit 72, and outputs them. The image signal (digital image signal) output from the signal input unit 71 is temporarily recorded in the frame memory 73.
The liquid crystal panel drive control unit 72 appropriately reads the digital image signals output from the signal input unit 71 and sequentially stored in the frame memory 73, performs predetermined processing on the read digital image signals, and performs the processing. A drive signal as image information corresponding to is output to the liquid crystal light valve 42 to form a predetermined optical image. Examples of the predetermined processing in the liquid crystal panel drive control unit 72 include image size adjustment processing such as enlargement / reduction, trapezoidal distortion correction processing, image quality adjustment processing, and gamma correction processing. Since each of these processes is a well-known technique, detailed description is abbreviate | omitted.

  The focus adjustment unit 74 is a focus position change unit 432A that constitutes the lens drive unit 432 of the projection optical device 43 in response to an operation signal input from the manual adjustment input unit 211 or the automatic adjustment input unit 212 that constitutes the operation unit 2. To adjust the focus of the projected image displayed on the screen Sc. As shown in FIG. 1, the focus adjustment unit 74 includes a manual adjustment control unit 741 and an automatic adjustment control unit 742 as a focus adjustment control unit, and a change range setting unit 743.

The manual adjustment control unit 741 outputs a predetermined control signal to the focus position changing unit 432A and drives the focus position changing unit 432A only when the operation signal from the manual adjustment input unit 211 constituting the operation unit 2 is input. Then, manual adjustment control is performed in which the focus position is changed by rotating the focus ring 431A by a rotation angle corresponding to the duration of the pressing state of the manual adjustment input unit 211.
In addition, the manual adjustment control unit 741 rotates the rotation angle of the focus ring 431A based on the signal output from the focus position detection unit 51 included in the rotation position detection unit 5 and the rotation described later set by the change range setting unit 743. Based on the position change range, the focus ring 431A is rotated within the rotation position change range.

The automatic adjustment control unit 742 drives the focus position changing unit 432A configuring the lens driving unit 432 until the projection image is in focus by an input operation of the automatic adjustment input unit 212 configuring the operation unit 2 by the user. Then, automatic adjustment control is performed to change the focus position by rotating the focus ring 431A. The automatic adjustment control unit 742 includes a pattern image display control unit 742A, a lens drive control unit 742B, an imaging drive control unit 742C, and an image analysis unit 742D.
The pattern image display control unit 742A outputs a predetermined control command to the liquid crystal panel drive control unit 72 according to an operation signal output from the automatic adjustment input unit 212 by an operation by the user, and is stored in the storage unit 76. The liquid crystal panel drive control unit 72 performs control to cause the liquid crystal light valve 42 to form an adjustment pattern image based on pattern image information described later.

The lens drive control unit 742B drives the focus position changing unit 432A to rotate the focus ring 431A by a predetermined angle (moves the focus position by a predetermined movement amount in the optical axis direction). The lens drive control unit 742B outputs a predetermined signal to the imaging drive control unit 742C each time the focus position changing unit 432A is driven to rotate the focus ring 431A by a predetermined angle.
Further, the lens drive control unit 742B rotates the rotation angle of the focus ring 431A based on the signal output from the focus position detection unit 51 included in the rotation position detection unit 5 and the rotation set later by the change range setting unit 743. Based on the position change range, the focus ring 431A is rotated within the rotation position change range.
Further, the lens drive control unit 742B changes the rotation direction of the focus ring 431A to the normal rotation direction (rotation direction in which the focus position is changed from the near end side to the far end side) and the reverse rotation direction (the focus position from the far end side to the near end). The rotation direction can be changed as appropriate.

The imaging drive control unit 742C drives the imaging unit 6 in accordance with a signal output from the lens drive control unit 742B, and images an adjustment pattern image projected on the screen Sc.
The image analysis unit 742D analyzes the adjustment pattern image based on signals sequentially output from the imaging unit 6, and determines whether or not the adjustment pattern image is in a focused state. Then, the image analysis unit 742D outputs a signal corresponding to the analyzed result to the lens drive control unit 742B.

  The change range setting unit 743 recognizes the rotation angle (detected zoom position) of the zoom ring 431C based on the signal output from the zoom position detection unit 52 included in the rotation position detection unit 5, and projects at the current detection zoom position. A rotation position change range is set as a focus position change range in which the focus ring 431A for effectively performing image focus adjustment (manual adjustment control and automatic adjustment control) can be rotated. As shown in FIG. 1, the change range setting unit 743 includes a proration information generation unit 743A and a focus limit position determination unit 743B.

  The apportionment information generation unit 743A has a wide end zoom position R2 (for example, 90 °) and a tele end zoom position R1 (for example, 0 °) based on later-described wide end position information and tele end position information stored in the storage unit 76. Apportionment information is generated by dividing the interval by the detected zoom position (current rotation angle of the zoom ring 431C) detected by the zoom position detector 52. Then, the apportionment information generation unit 743A outputs a signal corresponding to the generated apportionment information to the focus limit position determination unit 743B.

  The focus limit position determination unit 743B, based on the apportioning information, sets the shortest focus limit between the wide end shortest focus position and the tele end shortest focus position based on the later described wide end position information and tele end position information stored in the storage unit 76. The position (the rotation angle of the focus ring 431A when the projected image is in focus at the shortest projection distance defined by the specifications of the projection lens 431 at the detection zoom position) is determined, and the wide end position information and the tele end position are determined. The longest focus limit position between the wide end longest focus position and the tele end longest focus position based on information (the focus when the projected image is in focus at the maximum zoom distance at the detection zoom position and defined by the specifications of the projection lens 431) The rotation angle of the ring 431A) is determined. Then, the focus limit position determination unit 743B determines the range from the determined shortest focus limit position to the longest focus limit position as the rotation position change range, and sends a predetermined signal corresponding to the rotation position change range to the manual adjustment control unit 741 and The data is output to the automatic adjustment control unit 742.

  The zoom adjustment unit 75 outputs a predetermined control signal to the zoom position change unit 432B and drives the zoom position change unit 432B only when an operation signal from the zoom adjustment input unit 22 constituting the operation unit 2 is input. Then, zoom adjustment control is performed in which the zoom position is changed by rotating the zoom ring 431C by the rotation angle corresponding to the duration of the pressed state of the zoom adjustment input unit 22.

As shown in FIG. 1, the storage unit 76 includes a pattern image storage unit 761 and a position information storage unit 762.
The pattern image storage unit 761 stores pattern image information related to an adjustment pattern image for performing automatic adjustment control in the automatic adjustment control unit 742.
FIG. 3 is a diagram illustrating an example of the adjustment pattern image PF.
As shown in FIG. 3, the adjustment pattern image PF is a striped image in which vertical lines of white W and vertical lines of black B are alternately arranged.
As the adjustment pattern image, in addition to the adjustment pattern image PF shown in FIG. 3, for example, a stripe image in which white lines and black lines are alternately arranged in parallel may be used.

  The position information storage unit 762 stores wide end position information and tele end position information for setting the rotation position change range at the detected zoom position by the change range setting unit 743. Specifically, the wide end position information includes the wide end zoom position R2 (FIG. 2) corresponding to the rotation angle of the zoom ring 431C at the wide end where the contour of the projected image is maximum, and the zoom position is the wide end zoom position R2. In this case, the wide end shortest focus position corresponding to the rotation angle of the focus ring 431A when the projected image is in focus at the shortest projection distance defined by the specifications of the projection lens 431, and the specifications of the projection lens 431. The table structure is associated with the wide end longest focus position corresponding to the rotation angle of the focus ring 431A when the projected image is in focus at the longest projection distance. The tele end position information includes the tele end zoom position R1 (FIG. 2) corresponding to the rotation angle of the zoom ring 431C at the tele end where the contour of the projected image is minimum, and the zoom position is the tele end zoom position R1. In this case, the tele-end shortest focus position corresponding to the rotation angle of the focus ring 431A when the projection image is in focus at the shortest projection distance, and the focus ring when the projection image is in focus at the longest projection distance. It has a table structure in which the telephoto end longest focus position corresponding to the rotation angle of 431A is associated.

4 and 5 are diagrams for explaining a setting method of the wide end shortest focus position, the wide end longest focus position, the tele end shortest focus position, and the tele end longest focus position. In FIG. 4, the horizontal axis indicates the projection distance, and the vertical axis indicates the rotation angle (focus position) of the focus ring.
In the present embodiment, the wide end shortest focus position, the wide end longest focus position, the tele end shortest focus position, and the tele end longest focus position are set as follows. In the following, it is assumed that the shortest projection distance defined by the specification of the projection lens 431 is 1 m and the longest projection distance is 11 m.
First, when the projector 1 is manufactured, the worker places the projector 1 at a position separated from the screen Sc by a predetermined distance (for example, 2 m), activates the projector 1, and displays an adjustment pattern image on the screen Sc. . In addition, the operator rotates the zoom ring 431C constituting the projection lens 431 and positions it at the tele end zoom position R1. Then, the operator rotates the focus ring 431A to perform the focus adjustment so that the adjustment pattern image is in focus, and the rotation angle of the focus ring 431A (in which the adjustment pattern image is in focus at the predetermined distance) ( First focus position) is measured. In addition, the operator rotates the zoom ring 431C to be positioned at the wide end zoom position R2, performs focus adjustment in the same manner as described above, and rotates the focus ring 431A at which the adjustment pattern image is in focus at the predetermined distance ( Second focus position) is measured.

Thereafter, the operator is responsive to the measured first focus position and second focus position and the optical characteristics according to the specifications of the projection lens 431 (the relationship between the projection distance and the focus position that is the rotation angle of the focus ring 431A). Based on this, the wide end shortest focus position, the wide end longest focus position, the tele end shortest focus position, and the tele end longest focus position are calculated.
For example, the optical characteristics are given by the following formula 1 when the projection distance is D (m), the focal distance is f (m), and the rotation angle of the focus ring 431A is R (rad).

[Equation 1]
^{D = (- C1 · f 2} ) / (C2-R) + C3

  In Formula 1, C1 is a coefficient determined by the lens design and the units of D, R, and f. C2 is the lens position when the projection distance is ∞, and changes depending on the zoom position, which is the rotation angle of the zoom ring 431C. C3 is a constant determined by the lens design. Further, f is given by a function corresponding to the focus position that is the rotation angle of the focus ring 431A, the zoom position that is the rotation angle of the zoom ring 431C, and the like.

  That is, as shown in FIG. 4, the operator shows a curve indicating the relationship between the projection distance and the focus position at a predetermined zoom position (for example, the relationship at the tele end zoom position R1) according to the optical characteristics. The curve CL1 and the curve CL2) showing the relationship at the wide end zoom position R2 can be recognized. Specifically, C1, f, and C3 in Equation 1 above show values almost as designed for each individual projection lens 431, while C2 in Equation 2 above is a manufacturing error and margin for each individual projection lens 431. May fluctuate significantly. Then, by measuring the first focus position and the second focus position described above, the value of C2 unique to the projection lens 431 can be specified. In addition, by specifying the value of C2, a curve indicating the relationship between the projection distance and the focus position at a predetermined zoom position unique to the projection lens 431 based on the above formula 1 (for example, the curve at the tele end zoom position R1). A curve CL1 indicating the relationship and a curve C2) indicating the relationship at the wide end zoom position R2 can be recognized.

  The operator can also recognize the difference in focus position between two points with different projection distances based on the curve at the predetermined zoom position. For example, as shown in FIG. 4, on the curves CL1 and CL2 at the tele end zoom position R1 and the wide end zoom position R2, the focus positions (the first focus position and the first focus position) of the positions P1A and P2A corresponding to the predetermined distance. 2 focus positions), positions P1B and P2B corresponding to the shortest projection distance (1 m), and positions P1C and P2C corresponding to the longest projection distance (11 m), respectively. Differences GF1AB, GF1AC, GF2AB, GF2AC (each of GF1AB and GF2AB are negative values) from the respective P2C focus positions (tele end longest focus position and wide end longest focus position) can be recognized.

  Then, as shown in FIG. 5, the operator calculates the tele-end shortest focus position FP1B (rotation angle of the focus ring) by adding the difference GF1AB to the measured first focus position FP1A, and the first focus. By adding the difference GF1AC to the position FP1A, the tele end longest focus position FP1C (rotation angle of the focus ring) is calculated. Further, as shown in FIG. 5, the operator calculates the wide end shortest focus position FP2B (rotation angle of the focus ring) by adding the difference GF2AB to the measured second focus position FP2A, and the second focus. The wide end longest focus position FP2C (rotation angle of the focus ring) is calculated by adding the difference GF2AC to the position FP2A. Then, when the projector 1 is manufactured, the worker associates the wide end zoom position R2, the calculated wide end shortest focus position FP2B, and the wide end longest focus position FP2C with each other and stores them in the position information storage unit 762 as wide end position information. Let Similarly, the worker associates the tele end zoom position R1, the calculated tele end shortest focus position FP1B, and the tele end longest focus position FP1C with each other and stores them in the position information storage unit 762 as tele end position information.

  Note that the measurement of the first focus position and the second focus position is not limited to being performed using the projector 1 that is actually a product, and for example, a reference projection lens (master lens) having standard optical characteristics is mounted. You may implement using the projector made.

[1-2. (Focus adjustment control in projector)
Next, focus adjustment control in the projector 1 described above will be described.
Hereinafter, manual adjustment control by the manual adjustment control unit 741 and automatic adjustment control by the automatic adjustment control unit 742 will be described in order.

[1-2-1. (Manual adjustment control)
FIG. 6 is a flowchart for explaining manual adjustment control by the manual adjustment control unit 741.
First, the control device 7 constantly monitors whether or not an operation signal from the manual adjustment input unit 211 is input, that is, whether or not the user has operated the manual adjustment input unit 211 (processing S1).
In the process S1, when the control device 7 determines “Y”, that is, when it is determined that the manual adjustment input unit 211 is operated by the user, the detection based on the signal output from the zoom position detection unit 52 is performed. The zoom position is recognized (process S2: zoom position detection step).

After the process S2, the change range setting unit 743 detects the position at the detected zoom position based on the detected zoom position recognized in the process S2 and the wide end position information and the tele end position information stored in the position information storage unit 762. The shortest focus limit position and the longest focus limit position are determined, and a rotation position change range is set (step S3: change range setting step).
Specifically, FIGS. 7 and 8 are diagrams illustrating an example of a method for setting the rotational position change range.
First, the apportionment information generation unit 743A apportions between the wide end zoom position R2 and the tele end zoom position R1 based on the wide end position information and the tele end position information at the detected zoom position to generate apportionment information (processing S3A). For example, as shown in FIG. 7, when the tele end zoom position R1 is 0 ° and the wide end zoom position R2 is 90 °, the detected zoom position ZPA is between the tele end zoom position R1 and the wide end zoom position R2. To calculate a ratio (1: 1), and outputs a signal corresponding to the information on the ratio (proportional information) to the focus limit position determination unit 743B.

Next, the focus restriction position determination unit 743B recognizes a ratio based on the distribution information generated by the distribution information generation unit 743A. Then, the focus limit position determination unit 743B distributes the distance between the tele end shortest focus position and the wide end shortest focus position based on the wide end position information and the tele end position information by the recognized ratio and determines the shortest focus limit position ( Process S3B). For example, as shown in FIG. 8, when the tele end shortest focus position FP1B is 20 ° and the wide end shortest focus position FP2B is 40 °, the ratio between the tele end shortest focus position FP1B and the wide end shortest focus position FP2B is a ratio. (1: 1) is allocated and the shortest focus limit position F1 is determined as 30 °.
Similarly, the focus limit position determination unit 743B equally distributes the distance between the longest focus position at the tele end and the longest focus position at the wide end based on the wide end position information and the tele end position information as the longest focus limit position. Determine (processing S3B). For example, as shown in FIG. 8, when the tele end longest focus position FP1C is 50 ° and the wide end longest focus position FP2C is 70 °, the tele end longest focus position FP1C and the wide end longest focus position are the same as above. The distance between FP2C is prorated by a ratio (1: 1), and the longest focus limit position F2 is determined as 60 °.
Then, the focus limit position determination unit 743B sets a range from the shortest focus limit position F1 to the longest focus limit position F2 at the detected zoom position as the rotation position change range F12, and a predetermined signal corresponding to the rotation position change range F12. Is output to the manual adjustment control unit 741.

After the process S3, the manual adjustment control unit 741 recognizes the rotational position change range F12 based on the signal output from the change range setting unit 743. Further, the manual adjustment control unit 741 outputs a predetermined control signal to the focus position changing unit 432A, and performs manual adjustment control for changing the focus position by rotating the focus ring 431A at a predetermined rotation speed (processing S4). .
Specifically, the manual adjustment control unit 741 determines whether the operation of the manual adjustment input unit 211 by the user is an input operation of the fur button 211A or an input operation of the near button 211B. If the manual adjustment control unit 741 determines that the input operation is the near button 211B, the focus position changing unit 432A is driven so that the focus ring 431A rotates in the direction of the arrow A1 (FIG. 2), and the projection distance is set. When the image is short, the focus position is changed to the near end side where the projected image can be adjusted to the in-focus state. On the other hand, if the manual adjustment control unit 741 determines that the input operation is the fur button 211A, the focus adjustment unit 432A drives the focus position changing unit 432A so that the focus ring 431A rotates in the direction of the arrow A2 (FIG. 2). When the distance is long, the focus position is changed to the far end side where the projected image can be adjusted to the in-focus state.
Then, the user manually presses the far button 211A or the near button 211B while visually confirming the projection image displayed on the screen Sc, and manually enters the manual adjustment control unit 741 so that the projection image is in focus. Perform adjustment control.

After the process S4, the manual adjustment control unit 741 compares the detected focus position based on the signal output from the focus position detection unit 51 with the longest focus limit position F2 based on the recognized rotational position change range F12, and detects it. It is determined whether or not the focus position is the same as the longest focus restriction position F2, that is, whether or not the rotation position has reached the longest focus restriction position F2 due to the rotation of the focus ring 431A in the direction of arrow A2 in step S4. (Processing S5).
In the process S5, when the manual adjustment control unit 741 determines “Y”, that is, when it is determined that the rotation position of the focus ring 431A has reached the longest focus limit position F2, the focus position changing unit 432A is driven. Is stopped (step S8), and the manual adjustment control is terminated.

On the other hand, in the process S5, when the manual adjustment control unit 741 determines “N”, that is, when it is determined that the rotation position of the focus ring 431A has not reached the longest focus limit position F2, the detected focus position is determined. The shortest focus limit position F1 based on the recognized rotational position change range F12 is compared. Then, the manual adjustment control unit 741 determines whether or not the detected focus position is the same as the shortest focus restriction position F1, that is, the rotation position of the focus ring 431A in the direction of arrow A1 in the process S4 is the shortest focus restriction position. It is determined whether or not F1 has been reached (step S6).
In the process S6, when the manual adjustment control unit 741 determines “Y”, that is, when it is determined that the rotation position of the focus ring 431A has reached the shortest focus limit position F1, the focus position changing unit 432A is driven. Is stopped (step S8), and the manual adjustment control is terminated.

On the other hand, if the manual adjustment control unit 741 determines “N” in process S6, that is, if it is determined that the rotational position of the focus ring 431A has not reached the shortest focus limit position F1, the manual adjustment input unit It is determined whether or not the output of the operation signal from 211 has ended, that is, whether or not the operation of the manual adjustment input unit 211 by the user has ended (process S7).
In the process S7, when the manual adjustment control unit 741 determines “N”, that is, when it is determined that the operation of the manual adjustment input unit 211 by the user is continuously performed, the above-described process S4 is performed. -S7 is performed again. That is, the manual adjustment control unit 741 repeatedly performs the above-described processes S4 to S7 until the operation of the manual adjustment input unit 211 by the user is completed.
On the other hand, in the process S7, when the manual adjustment control unit 741 determines “N”, that is, when it is determined that the user has finished operating the manual adjustment input unit 211, the focus position changing unit 432A is driven. Is stopped (step S8), and the manual adjustment control is terminated.
Note that steps S4 to S8 described above correspond to the focus adjustment step according to the present invention.

  As described above, the manual adjustment control unit 741 performs manual adjustment control for changing the focus position within the rotation position change range F12 of the shortest focus limit position F1 to the longest focus limit position F2.

[1-2-2. (Automatic adjustment control)
FIG. 9 is a flowchart for explaining automatic adjustment control by the automatic adjustment control unit 742.
First, the control device 7 constantly monitors whether or not an operation signal from the automatic adjustment input unit 212 is input, that is, whether or not the automatic adjustment input unit 212 is operated by the user (processing S11).
In the process S11, when the control device 7 determines “Y”, that is, when it is determined that the automatic adjustment input unit 212 is operated by the user, the pattern image display control unit 742A performs the liquid crystal panel drive control unit 72. A predetermined control command is output to Then, the liquid crystal panel drive control unit 72 reads the pattern image information stored in the pattern image storage unit 761 and causes the liquid crystal light valve 42 to form an adjustment pattern image based on the pattern image information. Further, the adjustment pattern image formed via the projection lens 431 is enlarged and projected onto the screen Sc (processing S12).

After the process S12, the control device 7 recognizes the detected zoom position based on the signal output from the zoom position detection unit 52 as in the above-described process S2 (process S13: zoom position detection step).
After the process S13, the change range setting unit 743 performs the detection zoom position ZPA recognized in the process S13, the wide end position information and the tele end position information stored in the position information storage unit 762, similarly to the process S3 described above. Based on this, the shortest focus limit position F1 and the longest focus limit position F2 at the detected zoom position ZPA are determined, and the rotation position change range F12 is set (processing S14: change range setting step). Then, the change range setting unit 743 outputs a predetermined signal corresponding to the set rotational position change range F12 to the automatic adjustment control unit 742.

After the process S14, the lens drive control unit 742B recognizes the rotational position change range F12 based on the signal output from the change range setting unit 743. Further, the lens drive control unit 742B outputs a predetermined control signal to the focus position changing unit 432A, and rotates the focus ring 431A at every predetermined angle to change the focus position (processing S15).
After the process S15, the lens drive control unit 742B compares the detected focus position based on the signal output from the focus position detection unit 51 with the longest focus limit position F2 based on the recognized rotational position change range F12, and detects it. Whether or not the focus position is the same as the longest focus limit position F2, that is, the rotation position of the focus ring 431A in the normal rotation direction (arrow A2 direction (FIG. 2)) by the lens drive control unit 742B is the longest focus position. It is determined whether or not the limit position F2 has been reached (step S16).
In process S16, when the lens drive control unit 742B determines “Y”, that is, when it is determined that the rotation position of the focus ring 431A has reached the longest focus limit position F2, the rotation direction of the focus ring 431A is determined. The rotation is reversed (processing S18), and the rotation control of the focus ring 431A by the lens drive control unit 742B is changed from the normal rotation direction to the reverse rotation direction (arrow A1 direction (FIG. 2)). Then, the processes S15 and S16 are performed again.

On the other hand, if the lens drive control unit 742B determines “N” in process S16, that is, if it is determined that the rotational position of the focus ring 431A has not reached the longest focus limit position F2, the detected focus position is determined. Then, the shortest focus limit position F1 based on the recognized rotational position change range F12 is compared. Then, the lens drive control unit 742B determines whether or not the detected focus position is the same as the shortest focus limit position F1, that is, in the reverse direction of the focus ring 431A by the lens drive control unit 742B (arrow A1 direction (FIG. 2)). It is determined whether or not the rotation position has reached the shortest focus limit position F1 by the rotation control (step S17).
In process S17, when the lens drive control unit 742B determines “Y”, that is, when it is determined that the rotation position of the focus ring 431A has reached the shortest focus limit position F1, the rotation direction of the focus ring 431A is determined. The rotation is reversed (process S18), and the rotation control of the focus ring 431A by the lens drive control unit 742B is changed from the reverse rotation direction to the normal rotation direction. And processing S15-S17 is implemented again.

On the other hand, if the lens drive control unit 742B determines “N” in process S17, that is, if it is determined that the rotational position of the focus ring 431A has not reached the shortest focus limit position F1, the imaging drive control unit A predetermined signal is output to 742C. Then, the imaging drive control unit 742C drives the imaging unit 6 in accordance with the signal output from the lens drive control unit 742B to capture the adjustment pattern image projected on the screen Sc (processing S19).
After the process S19, the image analysis unit 742D recognizes the captured adjustment pattern image based on the signal output from the imaging unit 6, and performs an analysis of the adjustment pattern image (process S20).
For example, the image analysis unit 742D analyzes the adjustment pattern image as follows.
First, the image analysis unit 742D measures the brightness values of white W and black B of the adjustment pattern image PF shown in FIG. Then, the contrast value of the adjustment pattern image PF is calculated by taking the difference between the luminance value of white W and the luminance value of black B.

After the process S20, the image analysis unit 742D determines whether or not the adjustment pattern image is in an in-focus state according to the analysis result of the adjustment pattern image (process S21).
For example, the image analysis unit 742D compares the calculated contrast value with a predetermined reference value (contrast value in a focused state) and determines whether the calculated contrast value is the same as the reference value. judge.
In process S21, when the image analysis unit 742D determines “N”, that is, when it is determined that the adjustment pattern image is not in focus, the image analysis unit 742D outputs a predetermined signal to the lens drive control unit 742B. And processing S15-S20 is implemented again. That is, steps S15 to S20 are repeatedly performed until the adjustment pattern image is in focus.

On the other hand, if the image analysis unit 742D determines “Y” in process S21, that is, if it is determined that the adjustment pattern image is in focus, the image analysis unit 742D outputs a predetermined signal to the lens drive control unit 742B. . Then, the lens drive control unit 742B stops driving the focus position changing unit 432A and stops changing the focus position in accordance with a signal from the image analysis unit 742D (processing S22).
Note that steps S15 to S22 described above correspond to the focus adjustment step according to the present invention.

  As described above, the automatic adjustment control unit 742 changes the focus position within the rotation position change range F12 of the shortest focus limit position F1 to the longest focus limit position F2 to match the adjustment pattern image, similarly to the manual adjustment control. Automatic adjustment control is performed to position the focus position at the position where the focus state is reached.

In the first embodiment described above, the mechanical limit range R12 in which the focus position can be mechanically changed is adjusted by the shortest projection distance defined in the specification of the projection lens 431 in consideration of the manufacturing error of the projection lens 431. It is set so as to be wider than the range from the design shortest focus limit position that is in focus to the design longest focus limit position that is in focus at the longest projection distance. The change range setting unit 743 of the control device 7 then projects the longest projection from the shortest focus limit position F1 at which the projection image is in focus at the shortest projection distance at the current detected zoom position detected by the zoom position detection unit 52. Rotation that allows the focus ring 431A to rotate effectively the focus adjustment (manual adjustment control and automatic adjustment control) of the projection image within the range up to the longest focus limit position F2 where the projection image is in focus at a distance. It is set as the position change range F12. For this reason, the rotational position change range F12 can be set to a range narrower than the machine limit range R12. Then, the manual adjustment control unit 741 and the automatic adjustment control unit 742 recognize the detected focus position detected by the focus position detection unit 51, and within the rotational position change range F12 that is narrower than the machine limit range R12. Since focus adjustment control (manual adjustment control, automatic adjustment control) is performed by changing the focus position, the focus adjustment time in the focus adjustment control can be shortened.
Further, each time the change range setting unit 743 changes the zoom position by the zoom adjustment by the zoom adjustment unit 75, the change range setting unit 743 sets the rotation position change range F12 according to the changed zoom position. Focus adjustment control can always be performed within the effective rotation position change range F12 without changing the focus position to a focus position at which the projected image is not in focus.

  Here, in both of the manual adjustment control by the manual adjustment control unit 741 and the automatic adjustment control by the automatic adjustment control unit 742, the focus position is changed within the rotation position change range F12, so that the input operation of the operation unit 2 by the user is performed. Thus, when the manual adjustment control unit 741 performs manual adjustment control, the focus position is not changed to the focus position at which the projected image is not in focus, and the user can perform a wasteful input operation. Absent. Further, even when the automatic adjustment control unit 742 performs automatic adjustment control by an input operation of the operation unit 2 by the user, the focus position is not changed to a focus position at which the projected image is not in focus, The in-focus position can be determined efficiently and quickly. Therefore, it becomes very convenient for the user.

The position information storage unit 762 stores the wide end position information and the tele end position information, and the change range setting unit 743 uses the wide end shortest focus position FP2B and the wide end longest focus position based on the wide end position information and the tele end position information. The shortest focus limit position F1 and the longest focus limit position F2 are determined on the basis of the four focus positions of FP2C, tele end shortest focus position FP1B, and tele end longest focus position FP1C. For this reason, for example, each shortest focus limit position and each longest focus limit position corresponding to each zoom position are stored in the storage unit, and the change range setting unit stores the shortest focus limit position and longest focus limit position corresponding to the detected zoom position. The amount of information stored in the storage unit can be effectively reduced as compared with the configuration in which the rotational position change range is set by reading out from the storage unit.
Further, the change range setting unit 743 includes an apportionment information generation unit 743A and a focus limit position determination unit 743B, and generates apportionment information regarding a ratio of apportionment between the wide end zoom position R2 and the tele end zoom position R1 at the detection zoom position. The shortest focus limit position F1 is determined by apportioning the tele end shortest focus position FP1B and the wide end shortest focus position FP2B by the ratio, and the tele end longest focus position FP1C and the wide end longest focus position FP2C are apportioning by the ratio. Since the longest focus limit position F2 is determined, the determination of the shortest focus limit position F1 and the longest focus limit position F2 is easily performed with a simple configuration using the wide end position information and the tele end position information with a small amount of information. it can.

  Then, the change range setting unit 743 sets the shortest focus limit position F1 and the longest focus limit position F2 that are the rotation position change range F12 with the rotation angle of the focus ring 431A, and the manual adjustment control unit 741 and the automatic adjustment control unit 742 While the rotational position of the focus ring 431A is changed within the rotational position change range F12 while recognizing the detected rotational position of the focus ring 431A detected by the focus position detector 51, for example, the relative positions of a plurality of lenses Compared with a configuration in which the focus position (the position of the focus lens 431B in the optical axis direction) is detected and manual adjustment control and automatic adjustment control are performed, the configuration can be simplified and manual adjustment control and automatic adjustment control can be performed. Can be easily implemented.

  Further, the operator actually sets the projected image at a predetermined projection distance at the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C. For example, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide focus position FP2A are calculated based on the first focus position FP1A and the second focus position FP2A. Compared with the configuration in which the longest end focus position FP2C is a value actually measured at the shortest projection distance and the longest projection distance, the screen Sc and the projector 1 are set at an easy-to-handle projection distance such as 2 m, so that each focus position FP1B, FP1C, FP2B, FP2C Calculation can, thereby the efficiency of the work space at the time of manufacture of the projector 1.

  Furthermore, the first focus position FP1A and the second focus position FP2A are actually measured, and the focus positions FP1B, FP1C, FP2B, and FP2C are calculated based on the first focus position FP1A and the second focus position. For example, as compared with a configuration in which the focus positions FP1B, FP1C, FP2B, and FP2C defined by the specifications of the projection lens 431 are used as they are, each manufacturing error corresponds to the manufacturing error even when a manufacturing error occurs in the projection lens 431. The focus positions FP1B, FP1C, FP2B, and FP2C can be calculated, and the focus positions FP1B, FP1C, FP2B, and FP2C can be set to more accurate values. Therefore, the rotational position change range F12 can be set with higher accuracy based on the focus positions FP1B, FP1C, FP2B, and FP2C, which are highly accurate values, and focus adjustment control can be performed more favorably.

[2. Second Embodiment]
Next, 2nd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
[2-1. Projector configuration)
FIG. 10 is a block diagram illustrating a schematic configuration of a projector 1 ′ according to the second embodiment.
In the first embodiment, the operator measures the first focus position FP1A and the first focus position FP1A, the telephoto end shortest focus position FP1B, the telephoto end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C. It is calculated by calculation based on the two focus positions FP2A, and is stored in the position information storage unit 762 as wide end position information and tele end position information using these focus positions FP1B, FP1C, FP2B, and FP2C.
On the other hand, in the second embodiment, as shown in FIG. 10, the control device 7 ′ constituting the projector 1 ′ includes a signal input unit 71, a liquid crystal panel drive control unit 72, a frame memory 73, a focus adjustment unit 74, In addition to the zoom adjustment unit 75, a focus position determination unit 77 and a storage unit 76 'are provided. The storage unit 76 ′ includes a difference information storage unit 763 in addition to the pattern image storage unit 761 and the position information storage unit 762. Then, the control device 7 'itself calculates the focus positions FP1B, FP1C, FP2B, and FP2C, and uses the focus positions FP1B, FP1C, FP2B, and FP2C as position information storage units as wide end position information and tele end position information. 762 is stored. The configuration other than the control device 7 'is the same as that of the first embodiment.

  The difference information storage unit 763 is a curve CL1 (representing the relationship between the projection distance and the focus position at the tele end zoom position R1 that can be recognized according to the optical characteristics (for example, Equation 1) described in the first embodiment. 4), the focus position (first focus position) at the position P1A (FIG. 4) corresponding to a predetermined projection distance (for example, 2 m), the shortest projection distance (for example, 1 m), and the longest projection distance (for example, 11 m). ) Of the respective positions P1B and P1C (FIG. 4) corresponding to the focus positions (tele end shortest focus position, tele end longest focus position) GF1AB and GF1AC (FIGS. 4 and 5) corresponding to the zoom positions (telephoto). The first difference information is stored in association with the end zoom position R1). Similarly, the difference information storage unit 763 shows a curve CL2 (see FIG. 5) indicating the relationship between the projection distance and the focus position at the wide-end zoom position R2 that can be recognized according to the optical characteristics described in the first embodiment. 4), the focus position (second focus position) of the position P2A (FIG. 4) corresponding to a predetermined projection distance (for example, 2 m), the shortest projection distance (for example, 1 m), and the longest projection distance (for example, 11 m). Differences GF2AB, GF2AC (FIG. 4, FIG. 5) from the respective focus positions (wide end shortest focus position, wide end longest focus position) of the positions P2B, P2C (FIG. 4) corresponding to the zoom position (wide end) The second difference information is stored in association with the zoom position R2).

The focus position determination unit 77 calculates the focus positions FP1B, FP1C, FP2B, and FP2C. As shown in FIG. 10, the focus position determination unit 77 includes a focus position information acquisition unit 771 and a focus position calculation unit 772.
The focus position information acquisition unit 771 includes a first focus position FP1A (FIG. 5) at which the projection image is in focus at the tele end zoom position R1 and a predetermined projection distance (for example, 2 m), and the wide end zoom position R2. And a second focus position FP2A (FIG. 5) at which the projection image is in a focused state at a predetermined projection distance (for example, 2 m). In the present embodiment, the focus position information acquisition unit 771 acquires the focus positions detected by the focus position detection unit 51 as the first focus position FP1A and the second focus position FP2A.

As a configuration for acquiring the first focus position FP1A and the second focus position FP2A by the focus position information acquisition unit 771, besides the acquisition from the focus position detection unit 51, the following configuration may be adopted.
For example, a focus position setting input unit is provided in the operation unit 2, and the user is allowed to set and input the first focus position FP1A and the second focus position FP2A by the focus position setting input unit. Then, the focus position information acquisition unit 771 acquires the first focus position FP1A and the second focus position FP2A based on the operation signal output from the focus position setting input unit.
Further, for example, information on the first focus position FP1A and the second focus position FP2A is input from an external device via the signal input unit 71, and the focus position information acquisition unit 771 is based on the information, and the first focus position FP1A and the second focus position FP1A are input. The 2-focus position FP2A is acquired.
Then, the focus position information acquisition unit 771 outputs a signal corresponding to the acquired first focus position FP1A and second focus position FP2A to the focus position calculation unit 772.

  The focus position calculation unit 772 includes the first focus position FP1A and the second focus position FP2A acquired by the focus position information acquisition unit 771, and the first difference information and the second difference information stored in the difference information storage unit 763. Based on this, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C are calculated.

[2-2. (Wide end position information and tele end position information setting method)
Next, a setting method of wide end position information and tele end position information in the present embodiment will be described.
First, when the projector 1 ′ is manufactured, the worker arranges the projector 1 ′ at a position separated from the screen Sc by a predetermined distance (for example, 2 m). Thereafter, the operator operates the operation unit 2 of the projector 1 ′ to shift from the normal mode for normally driving the projector 1 ′ to the setting mode for setting the wide end position information and the tele end position information. Perform an input operation to the effect. The control device 7 'inputs the operation signal output from the operation unit 2, and shifts the projector 1' from the normal mode to the setting mode in accordance with a predetermined program stored in a memory (not shown) and performs the following processing. To do.

The control device 7 ′ drives the zoom position changing unit 432B to rotate the zoom ring 431C to position it at the tele end zoom position R1.
Next, the control device 7 ′ performs the automatic adjustment control described in the first embodiment, and positions the focus position at the first focus position FP1A where the adjustment pattern image is in focus at the predetermined distance.
Next, the focus position information acquisition unit 771 acquires the first focus position FP1A based on the signal output from the focus position detection unit 51. Then, the focus position information acquisition unit 771 outputs a signal corresponding to the first focus position FP1A to the focus position calculation unit 772.
Next, the focus position calculation unit 772 recognizes the tele end zoom position R1 based on the signal output from the zoom position detection unit 52, and the first information corresponding to the recognized tele end zoom position R1 from the difference information storage unit 763. The differences GF1AB and GF1AC based on the difference information are read out.
Thereafter, the focus position calculation unit 772 adds the read differences GF1AB and GF1AC to the first focus position FP1A based on the signal output from the focus position information acquisition unit 771, thereby making the tele end shortest focus position FP1B ( 5) and the tele-end longest focus position FP1C (FIG. 5) are calculated. The focus position calculation unit 772 associates the tele end zoom position R1, the calculated tele end shortest focus position FP1B, and the tele end longest focus position FP1C with each other and stores them in the position information storage unit 762 as tele end position information.

Thereafter, in substantially the same manner as described above, the control device 7 ′ drives the zoom position changing unit 432B to rotate the zoom ring 431C to be positioned at the wide end zoom position R2.
Next, the control device 7 ′ performs the automatic adjustment control described in the first embodiment, and positions the focus position at the second focus position FP2A where the adjustment pattern image is in focus at the predetermined distance.
Next, the focus position information acquisition unit 771 acquires the second focus position FP2A based on the signal output from the focus position detection unit 51. Then, the focus position information acquisition unit 771 outputs a signal corresponding to the second focus position FP2A to the focus position calculation unit 772.
Next, the focus position calculation unit 772 recognizes the wide end zoom position R2 based on the signal output from the zoom position detection unit 52, and the second information corresponding to the recognized wide end zoom position R2 from the difference information storage unit 763. The differences GF2AB and GF2AC based on the difference information are read out.
After that, the focus position calculation unit 772 adds the read differences GF2AB and GF2AC to the second focus position FP2A based on the signal output from the focus position information acquisition unit 771, respectively, so that the wide end shortest focus position FP2B ( 5) and the wide end longest focus position FP2C (FIG. 5) are calculated. Then, the focus position calculation unit 772 associates the wide end zoom position R2, the calculated wide end shortest focus position FP2B, and the wide end longest focus position FP2C with each other and stores them in the position information storage unit 762 as wide end position information.

  The focus adjustment control in the projector 1 ′ can be performed in the same manner as the focus adjustment control (manual adjustment control and automatic adjustment control) described in the first embodiment, and thus the description thereof is omitted.

  In the second embodiment described above, as compared with the first embodiment, the difference between the first focus position FP1A and the second focus position FP2A detected by the focus position detection unit 51 and the projector 1 ′ itself is the difference information. Based on the first difference information and the second difference information stored in the storage unit 763, the wide end shortest focus position FP2B, the wide end longest focus position FP2C, the tele end shortest focus position FP1B, and the tele end longest focus position FP1C are calculated. Since the tele-end position information and the wide-end position information based on the calculated four focus positions are stored in the position information storage unit 762, the first focus position FP1A and the second focus position FP2A are produced when the projector 1 ′ is manufactured. Based on each focus position FP1B, FP1C, FP2 Without causing the operator to perform the operation of calculating B and FP2C, the projector 1 'can be easily manufactured, and the convenience can be improved.

[3. Third Embodiment]
Next, 3rd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
[3-1. Projector configuration)
FIG. 11 is a block diagram illustrating a schematic configuration of a projector 1 ″ according to the third embodiment.
In the first embodiment, the control device 7 uses the shortest focus limit position F1 and the longest focus limit position F2, which are the rotation position change range F12, as the tele end shortest focus position FP1B stored in the position information storage unit 762, the tele end. It is calculated using the longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C.
On the other hand, in the third embodiment, as shown in FIG. 11, in the control device 7 ″ constituting the projector 1 ″, the change range setting unit 743 ″ of the focus adjustment unit 74 ″ generates the corresponding characteristic information. Unit 743C and a focus limit position determination unit 743D. The storage unit 76 ″ includes a characteristic information storage unit 764 and a projection distance information storage unit 765 instead of the position information storage unit 762, and is the shortest rotation position change range F12. The focus limit position F1 and the longest focus limit position F2 are calculated by a method different from that in the first embodiment. The configurations other than the change range setting unit 743 ″ and the storage unit 76 ″ are the same as those in the first embodiment.

The characteristic information storage unit 764 stores characteristic information related to optical characteristics (relationship between the projection distance and the focus position that is the rotation angle of the focus ring at a predetermined zoom position) according to the specifications of the projection lens 431. For example, as the characteristic information, information on the optical characteristic (for example, Formula 1) described in the first embodiment can be exemplified. In Equation 1, the design value of the projection lens 431 can be adopted as C1, C2, C3, and f.
The projection distance information storage unit 765 stores projection distance information related to the shortest projection distance (for example, 1 m) and the longest projection distance (for example, 11 m) defined by the specification of the projection lens 431.

Corresponding characteristic information generation unit 743C indicates the relationship between the projection distance at the detected zoom position detected by zoom position detecting unit 52 and the focus position based on the characteristic information stored in characteristic information storage unit 764. Generate information. Then, the correspondence characteristic information generation unit 743C outputs a signal corresponding to the generated correspondence characteristic information to the focus limit position determination unit 743D.
The focus limit position determination unit 743D is detected by the zoom position detection unit 52 based on the correspondence characteristic information generated by the correspondence characteristic information generation unit 743C and the projection distance information stored in the projection distance information storage unit 765. The shortest focus restriction position F1 and the longest focus restriction position F2 at the detected zoom position are determined. Then, the focus limit position determination unit 743D determines the range from the determined shortest focus limit position F1 to the longest focus limit position F2 as the rotation position change range F12, and manually outputs a predetermined signal corresponding to the rotation position change range F12. The data is output to the adjustment control unit 741 and the automatic adjustment control unit 742.

[3-2. (Focus adjustment control in projector)
Next, focus adjustment control in the projector 1 '' described above will be described.
Hereinafter, as in the first embodiment, manual adjustment control by the manual adjustment control unit 741 and automatic adjustment control by the automatic adjustment control unit 742 will be described in order.

[3-2-1. (Manual adjustment control)
FIG. 12 is a flowchart for explaining manual adjustment control by the manual adjustment control unit 741.
The manual adjustment control of this embodiment is different in the setting process (S3: change range setting step) of the shortest focus limit position F1 and the longest focus limit position F2, which are the rotation position change range F12 described in the first embodiment. Only the process of setting the rotational position change range F12 (S33: change range setting step) will be described below. The other processes S1, S2, S4 to S8 are the same as those in the first embodiment, and a description thereof is omitted.

In the process S33, the change range setting unit 743 ″ determines the shortest focus limit position F1 and the longest focus limit position F2 at the detected zoom position recognized in the process S2, and sets the rotation position change range F12.
Specifically, FIG. 13 is a diagram illustrating an example of a method for setting the rotational position change range.
First, the corresponding characteristic information generation unit 743C reads characteristic information (for example, Equation 1) stored in the characteristic information storage unit 764, converts the read characteristic information into characteristic information corresponding to the recognized detected zoom position, That is, correspondence characteristic information indicating the relationship between the projection distance at the recognized detected zoom position and the focus position is generated (processing S33A). For example, as shown in FIG. 13, the correspondence characteristic information generation unit 743C, based on the characteristic information (Equation 1) stored in the characteristic information storage unit 764, calculates the projection distance and the focus position at the recognized detected zoom position. Corresponding characteristic information corresponding to the curve CL0 indicating the relationship is generated. Then, the correspondence characteristic information generation unit 743C outputs a signal corresponding to the generated correspondence characteristic information to the focus limit position determination unit 743D.

The focus restriction position determination unit 743D recognizes the correspondence characteristic information based on the signal output from the correspondence characteristic information generation unit 743C. The focus limit position determination unit 743D recognizes the shortest projection distance and the longest projection distance based on the projection distance information stored in the projection distance information storage unit 765. Then, the focus limit position determination unit 743D determines the focus position corresponding to the shortest projection distance as the shortest focus limit position based on the recognized correspondence characteristic information, the shortest projection distance, and the longest projection distance, and corresponds to the longest projection distance. The focus position to be determined is determined as the longest focus limit position (processing S33B). For example, as illustrated in FIG. 13, the focus limit position determination unit 743D determines the focus position corresponding to the shortest projection distance (for example, 1 m) on the curve CL0 according to the corresponding characteristic information as the shortest focus limit position F1, and sets the longest The focus position corresponding to the projection distance (for example, 11 m) is determined as the longest focus limit position F2.
Then, the focus limit position determination unit 743D determines the range from the shortest focus limit position F1 to the longest focus limit position F2 at the detected zoom position as the rotation position change range F12, and a predetermined signal corresponding to the rotation position change range F12. Is output to the manual adjustment control unit 741.

[3-2-2. (Automatic adjustment control)
FIG. 14 is a flowchart illustrating automatic adjustment control by the automatic adjustment control unit 742.
The automatic adjustment control of the present embodiment is replaced with the setting process (process S14: change range setting step) of the shortest focus limit position F1 and the longest focus limit position F2, which is the rotation position change range F12 described in the first embodiment. As shown in FIG. 14, the above-described process S33 is performed. Other processes S11 to S13 and S15 to S22 are the same as those in the first embodiment.

  In the third embodiment described above, compared to the first embodiment and the second embodiment, the change range setting unit 743 ″ includes a corresponding characteristic information generation unit 743C and a focus limit position determination unit 743D. Based on the characteristic information stored in the characteristic information storage unit 764, corresponding characteristic information indicating the relationship between the projection distance at the detected zoom position and the focus position is generated, and stored in the corresponding characteristic information and projection distance information storage unit 765. The shortest focus restriction position F1 and the longest focus restriction position F2 are determined based on the projection distance information. As a result, information on the shortest wide end focus position FP2B, the longest wide end focus position FP2C, the tele end shortest focus position FP1B, and the tele end longest focus position FP1C and information on the differences GF1AB, GF1AC, GF2AB, GF2AC can be obtained at the time of manufacture of the projector. There is no need for the operator to actually measure or calculate the information and store the information in the storage unit. Only the characteristic information and the projection distance information defined by the specifications of the projection lens 431 are stored in the storage unit 76 ″. In other words, the work at the time of manufacturing the projector 1 ″ can be facilitated, and the convenience can be improved.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
In each of the embodiments, the shortest projection distance and the longest projection distance of the projection lens 431 are set to be the same (for example, the shortest projection distance is 1 m and the longest projection distance is 11 m) even when the zoom position is changed. ing. However, the present invention is not limited to the setting of the shortest projection distance and the longest projection distance as described above, but can be applied to a configuration in which the shortest projection distance and the longest projection distance are set differently according to the zoom position. For example, at the tele end zoom position R1, the shortest projection distance is 1.2 m and the longest projection distance is 12 m. At the wide end zoom position R2, the shortest projection distance is 1 m, and the longest projection distance is 10 m. With such a configuration, the shortest projection distance (longest projection distance) can be set according to the application, and the degree of design freedom in the projector 1 can be improved.

In each of the embodiments described above, the change range setting unit 743 determines the shortest focus limit position F1 and the longest focus limit position F2 based on the wide end position information and the tele end position information stored in the position information storage unit 762, and rotates the rotation position. The change range F12 is set, and the change range setting unit 743 '' is based on the characteristic information and the projection distance information stored in the characteristic information storage unit 764 and the projection distance information storage unit 765, and the shortest focus limit position F1 and the longest focus limit position. Although the rotational position change range F12 is set by determining F2, the present invention is not limited to this, and for example, the following configuration may be adopted.
For example, each zoom position from the tele end zoom position R1 to the wide end zoom position R2 and each shortest focus limit position and each longest focus limit position corresponding to each zoom position are associated with each other and stored in advance in the storage unit. deep. Then, the change range setting unit reads the shortest focus limit position and the longest focus limit position corresponding to the detected zoom position detected by the zoom position detection unit 52 from the storage unit, and reads the longest focus limit position from the read shortest focus limit position. The position up to the position is set as the rotation position change range which is the focus position change range.

  In each of the above embodiments, the focus position is changed within the rotation position change range F12 in both the manual adjustment control and the automatic adjustment control in the manual adjustment control unit 741 and the automatic adjustment control unit 742. However, the present invention is not limited to this. For example, a configuration in which the focus position is changed within the rotation position change range F12 in only one of manual adjustment control and automatic adjustment control may be employed.

In the first embodiment, the operator calculates the first focus position FP1A and the second focus position FP2A actually measured and the optical characteristics of the projection lens 431, so that the tele-end shortest focus position FP1B, Although the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C have been calculated, the present invention is not limited to this, and the following configuration, for example, may be employed.
For example, similarly to the measurement of the first focus position FP1A and the second focus position FP2A, the focus adjustment is performed at the telephoto end and at the shortest projection distance to measure the telephoto end shortest focus position FP1B. The focus adjustment is performed at the projection distance to measure the longest focus position FP1C at the tele end, the focus adjustment is performed at the shortest projection distance at the wide end, and the shortest focus position FP2B at the wide end is measured. The focus adjustment is performed at the projection distance to measure the wide end longest focus position FP2C. With such a configuration, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C are actually measured values, and each focus in the first embodiment The value is more accurate than the position. For this reason, the rotational position change range at the detected zoom position can be set with higher accuracy using each focus position that is a highly accurate value, and focus adjustment can be performed more favorably.
Further, for example, the focus positions FP1B, FP1C, FP2B, and FP2C defined by the specifications of the projection lens 431 may be used as they are.

In the second embodiment, the difference information storage unit 763 includes information on the differences GF1AB and GF1AC between the first focus position FP1A, the tele end shortest focus position FP1B, and the tele end longest focus position FP1C, and the second focus position FP2A and the wide. Information on the differences GF2AB and GF2AC between the shortest end focus position FP2B and the widest longest focus position FP2C is stored, but the present invention is not limited to this, and the following configuration may be employed.
For example, the difference information storage unit 763 stores information on each difference between the first focus position FP1A, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C. Remember. Then, the focus position information acquisition unit 771 acquires only the first focus position FP1A from the focus position detection unit 51, and the focus position calculation unit 772 stores the acquired first focus position FP1A in the difference information storage unit 763. By adding the differences based on the information, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C are calculated.

Further, for example, the difference information storage unit 763 relates to each difference between the second focus position FP2A and the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C. Store information. The focus position information acquisition unit 771 acquires only the second focus position FP2A from the focus position detection unit 51, and the focus position calculation unit 772 stores the acquired second focus position FP2A in the difference information storage unit 763. By adding the differences based on the information, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C are calculated.
With the above configuration, when the projector 1 ′ is manufactured, the focus position is adjusted to the first focus position FP1A or the zoom position by positioning the zoom position at the tele end zoom position R1 or the wide end zoom position R2. By positioning at the second focus position FP2A, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C can be calculated, and each focus position can be calculated more quickly. The projector 1 ′ can be manufactured more quickly.

  In the second embodiment, when the projector 1 ′ is manufactured, the control device 7 ′ calculates the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C. Thus, the tele end position information and the wide end position information based on each focus position are stored in the position information storage unit 762. However, the present invention is not limited to this, and for example, focus adjustment control (manual adjustment control, automatic adjustment control) is performed. When performing, the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C are calculated, and the tele end position information and the wide end based on each focus position are calculated. The position information is stored in the position information storage unit 762. May be used. At this time, when the projector 1 ′ is manufactured, focus position information regarding the first focus position FP1A and the second focus position FP2A is stored in the storage unit 76 ′ or the like in advance. When starting the focus adjustment control, the focus position calculation unit 772 calculates the tele end shortest focus position FP1B, the tele end longest focus position FP1C, the wide end shortest focus position FP2B, and the wide end longest focus position FP2C. Tele end position information and wide end position information based on each focus position are stored in the position information storage unit 762.

In the first embodiment and the second embodiment, the first focus position FP1A is a focus position measured by performing focus adjustment when the telephoto end is at a projection distance of 2 m, and the second focus The position FP2A is a focus position measured by performing focus adjustment when the projection distance is 2 m at the wide end, but is not limited thereto, and may be the following focus position.
For example, the first focus position FP1A is a focus position measured by performing focus adjustment when the telephoto end is the shortest projection distance.
Further, for example, the first focus position FP1A is a focus position measured by performing focus adjustment when the telephoto end is the longest projection distance.
Further, for example, the second focus position FP2A is set to a focus position measured by performing focus adjustment when the wide end is the shortest projection distance.
Furthermore, for example, the second focus position FP2A is set to a focus position measured by performing focus adjustment at the wide end and the longest projection distance.

  In the third embodiment, the information related to Equation 1 is adopted as the characteristic information, and the design values are adopted as C1, C2, C3, and f in Equation 1, but the present invention is not limited to this. For example, as in the first embodiment and the second embodiment, by measuring the first focus position and the second focus position, the value of C2 having a large variation is specified for each projection lens 431, and C2 Instead of the design value, the C2 value unique to the specified projection lens 431 is adopted. The rotational position change range F12 can be determined with higher accuracy by using Equation 1 that employs the value of C2 thus specified.

  In the above embodiment, a transmissive liquid crystal panel (liquid crystal light valve 42) is used. However, the present invention is not limited to this, and a reflective liquid crystal panel may be used, or a digital micromirror device (Texas). -Trademark of Instrument Corporation) may be adopted.

The best configuration for implementing the present invention has been disclosed in the above description, but the present invention is not limited to this. That is, the present invention has been illustrated and described primarily with respect to particular embodiments, but is not limited to the embodiments described above without departing from the scope and spirit of the present invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limited to the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.

  The projector of the present invention is useful as a projector used for presentations and home theaters because the focus adjustment time by the focus adjustment control can be shortened and the focus adjustment control can be performed within an effective focus position change range.

1 is a block diagram showing a schematic configuration of a projector according to a first embodiment. The figure which shows typically the principal part of the projection lens in the said embodiment. The figure which shows an example of the adjustment pattern image in the said embodiment. The figure for demonstrating the setting method of the wide end shortest focus position, the wide end longest focus position, the tele end shortest focus position, and the tele end longest focus position in the embodiment. The figure for demonstrating the setting method of the wide end shortest focus position, the wide end longest focus position, the tele end shortest focus position, and the tele end longest focus position in the embodiment. The flowchart explaining the manual adjustment control by the manual adjustment control part in the said embodiment. The figure which shows an example of the setting method of the rotation position change range in the said embodiment. The figure which shows an example of the setting method of the rotation position change range in the said embodiment. The flowchart explaining the automatic adjustment control by the automatic adjustment control part in the said embodiment. The block diagram which shows schematic structure of the projector in 2nd Embodiment. The block diagram which shows schematic structure of the projector in 3rd Embodiment. The flowchart explaining the manual adjustment control by the manual adjustment control part in the said embodiment. The figure which shows an example of the setting method of the rotation position change range in the said embodiment. The flowchart explaining the automatic adjustment control by the automatic adjustment control part in the said embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1 ', 1' '... Projector, 2 ... Operation part (setting input part), 41 ... Light source device, 42 ... Liquid crystal light valve (light modulation element), 43 ... Projection Optical device 51... Focus position detector 52. Zoom position detector 431. Projection lens 431 A Focus ring 431 C Zoom ring 432 A Focus position change unit 432B ... zoom position changing unit, 741 ... manual adjustment control unit (focus adjustment control unit), 742 ... automatic adjustment control unit (focus adjustment control unit), 743, 743 "... change range Setting unit, 743A ... Prorated information generating unit, 743B, 743D ... Focus limit position determining unit, 743C ... Corresponding characteristic information generating unit, 762 ... Position information storage unit, 763 ... Difference information Storage unit, 764... Characteristic information storage unit, 765... Projection distance information storage unit, 771... Focus position information acquisition unit, 772... Focus position calculation unit, F1. F2: Longest focus limit position, F12: Rotation position change range (focus position change range), FP1A: First focus position, FP2A: Second focus position, FP1B: Tele end shortest focus Position, FP1C: tele end longest focus position, FP2B: wide end shortest focus position, FP2C: wide end longest focus position, R1: tele end zoom position, R2: wide end zoom position, Sc: Screen, ZPA: Detection zoom position, S2, S13: Zoom position detection step, S3, S14, S33 ... change range setting step, S4~S8, S15~S22 ··· focus adjustment step.

Claims (8)

A projector comprising: a light modulation element that modulates a light beam emitted from a light source according to image information to form an optical image; and a projection optical device that enlarges and projects the optical image on a screen.
The projection optical apparatus includes a plurality of lenses, a projection lens that magnifies and projects the optical image onto a screen via the plurality of lenses, and the plurality of the projection optical devices for performing focus adjustment of the projected image that is magnified and projected onto the screen. A focus position changing unit that changes the focus position that is the relative position of the lens, and a zoom position changing unit that changes the zoom position that is the relative position of the plurality of lenses in order to perform zoom adjustment of the projection image. ,
A focus position detector for detecting the focus position;
A zoom position detector for detecting the zoom position;
Shortest focus restriction where the projected image is in focus when the projection distance to the screen is the shortest projection distance defined by the specifications of the projection lens at the detected zoom position detected by the zoom position detection unit A focus position change range in which the focus position can be changed from a position to a longest focus limit position where the projection image is in focus when the projection distance is the longest projection distance defined by the specifications of the projection lens. A change range setting section to be set;
A setting input unit for setting and inputting focus adjustment information for performing the focus adjustment;
A focus adjustment control unit that performs focus adjustment control that drives the focus position change unit based on the focus adjustment information to change the focus position;
The focus adjustment control unit performs the focus adjustment control within the focus position change range based on the detected focus position detected by the focus position detection unit and the focus position change range. projector. The projector according to claim 1, wherein
Wide end zoom position where the projected image is the maximum image, Wide end shortest focus position where the projected image is in focus at the shortest projection distance when the zoom position is the wide end zoom position, and the longest Wide end position information associated with the longest longest focus position at which the projected image is in focus at the projection distance, the tele end zoom position at which the projected image is the minimum contour, and the zoom position is the tele end zoom position The tele-end shortest focus position at which the projection image is in focus at the shortest projection distance and the tele-end longest focus position at which the projection image is in focus at the longest projection distance. A location information storage unit for storing location information;
The change range setting unit
An apportionment information generating unit that generates apportionment information obtained by apportioning the wide end zoom position and the tele end zoom position based on the wide end position information and the tele end position information at the detected zoom position;
Based on the apportionment information, the shortest focus limit position between the wide end shortest focus position and the tele end shortest focus position based on the wide end position information and the tele end position information, the wide end position information and the tele end position. A projector, comprising: a focus limit position determination unit that determines the longest wide end focus position and the longest focus limit position between the tele end longest focus positions based on end position information. The projector according to claim 2,
A first focus position where the projected image is in focus when the zoom position is the tele end zoom position and the projection distance is a predetermined distance, and the zoom position is the wide end zoom position and the projection distance Is the predetermined distance focus position of at least one of the second focus positions where the projected image is in focus when the predetermined distance is, the tele end shortest focus position, the tele end longest focus position, and the wide A difference information storage unit for storing difference information regarding each difference between the end shortest focus position and the wide end longest focus position;
A focus position information acquisition unit for acquiring focus position information regarding the predetermined distance focus position;
Based on the focus position information and the difference information, the tele end shortest focus position, the tele end longest focus position, the wide end shortest focus position, and the wide end longest focus position are calculated, and each calculated focus position is calculated. And a focus position calculation unit which stores the tele end position information and the wide end position information based on the position information storage unit. The projector according to claim 1, wherein
An optical system defined by the specifications of the projection lens that enables the focus position at which the projected image is in focus when the zoom position is positioned at a predetermined zoom position and the projection distance is a predetermined distance. A characteristic information storage unit for storing characteristic information about the characteristic;
A projection distance information storage unit that stores projection distance information related to the longest projection distance and the shortest projection distance;
The change range setting unit
A corresponding characteristic information generating unit that generates corresponding characteristic information indicating a relationship between the projection distance at the detected zoom position and the focus position based on the characteristic information;
A projector, comprising: a focus restriction position determination unit that determines the shortest focus restriction position and the longest focus restriction position based on the correspondence characteristic information and the projection distance information. The projector according to any one of claims 1 to 4,
The focus adjustment information includes manual adjustment information indicating that the focus position is changed by a predetermined amount, or automatic adjustment information indicating that the relative positions of the plurality of lenses are changed to a focus position at which the projection image is in focus. And
The focus adjustment control unit drives the focus position changing unit based on the manual adjustment information to change the focus position by a predetermined amount, and the projection image is focused based on the automatic adjustment information. Automatic adjustment control for changing the focus position by driving the focus position changing unit until the state is reached is performed, and is detected by the focus position detection unit when performing the manual adjustment control and the automatic adjustment control. A projector that changes the focus position within the focus position change range based on a detected focus position and the focus position change range. The projector according to any one of claims 1 to 5,
The projection lens accommodates and holds at least one of the plurality of lenses, and is configured to be rotatable around the lens optical axis of the plurality of lenses, and rotates to change the focus position and the zoom position, respectively. Consists of enabling focus ring and zoom ring,
The focus position changing unit and the zoom position changing unit are configured to rotate the focus ring and the zoom ring, respectively.
The focus position detection unit and the zoom position detection unit are configured to be able to detect rotation positions of the focus ring and the zoom ring,
The change range setting unit sets the rotation limit position of the focus ring corresponding to the shortest focus limit position and the longest focus limit position at the detection zoom position as the focus position change range,
The focus adjustment control unit is configured to control the focus adjustment within a range of each rotation limit position of the focus ring based on the detected rotation position of the focus ring and the focus position change range detected by the focus position detection unit. The projector characterized by implementing. The projector according to any one of claims 1 to 6,
The projector, wherein the shortest projection distance and the longest projection distance are set to be different depending on the zoom position. A light modulation element that modulates a light beam emitted from a light source according to image information to form an optical image, and a projection lens that has a plurality of lenses and projects the optical image on a screen through the plurality of lenses, A focus position changing unit that changes a focus position, which is a relative position of the plurality of lenses, in order to perform focus adjustment of the projection image enlarged and projected on the screen, and the plurality of lenses in order to perform zoom adjustment of the projection image. A projector control method including a projection optical device including a zoom position changing unit that changes a zoom position that is a relative position of a lens,
A zoom position detecting step for detecting the zoom position;
In the detected detection zoom position, when the projection distance to the screen is the shortest projection distance defined by the specifications of the projection lens, the projection distance is from the shortest focus limiting position where the projection image is in focus. A change range setting step for setting a focus position change range in which the focus position can be changed to the longest focus limit position where the projected image is in focus when the longest projection distance is defined by the specifications of the projection lens; ,
A projector control method comprising: a focus adjustment step of driving the focus position change unit to change the focus position within the focus position change range when performing the focus adjustment.

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