JP2008258732A - Camera with projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera with a projector which can suitably control a light emitting part independently of the on/off of the light emitting part in controlling the lighting of the light emitting part according to brightness. <P>SOLUTION: The camera with the projector is provided with a projection unit 200 for illuminating a modulation element 222 by the light emitting part 223 and projecting an optical image, an imaging unit 100 for imaging an object image and outputting an image signal, a brightness detection means 101 for detecting brightness by using the image signal, and a control means 101 for controlling the lighting of the light emitting part 223 according to the brightness detected by the brightness detection means by using an image signal obtained by imaging a wider range by the imaging unit 100, the range being wider than a projection range of the projection unit 200. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a camera equipped with a projector.

  Japanese Patent Application Laid-Open No. H10-228561 discloses a portable phone including a CCD camera, an optical sensor, and a light emitting diode. According to the prior art, the light sensor detects the illuminance near the subject and automatically turns on the light emitting diode according to the illuminance.

JP 2001-320461 A

  When a light emitting diode that is automatically turned on is used as a flashlight, there are the following problems. That is, when the light emitting diode is turned on, the illuminance in the vicinity of the subject increases, so that it may be determined that the light emitting diode is not required to be turned on.

(1) A camera with a projector according to the present invention includes a projection unit that illuminates a modulation element with a light emitting unit to project an optical image, an imaging unit that captures a subject image and outputs an image signal, and a brightness using the image signal. Brightness detecting means for detecting the brightness, and control means for controlling lighting of the light emitting unit according to the brightness detected by the brightness detecting means using an image signal obtained by imaging a wider range than the projection range of the projection unit by the imaging unit. It is characterized by providing.
(2) In the camera with a projector according to claim 1, it is preferable that the image pickup unit repeatedly picks up an image over a wider range than a projection range by the projection unit at a predetermined interval.
(3) In the camera with a projector according to claim 1 or 2, it is preferable that the projection unit performs modulation control on the modulation element so as to increase a projection light level.
(4) In the camera with a projector according to any one of claims 1 to 3, it is preferable that the control unit turns on the light emitting unit when the brightness is lower than the first determination value.
(5) In the camera with a projector according to any one of claims 1 to 3, the control unit blinks the light emitting unit when the brightness is lower than the first determination value, and the brightness is the first. It is preferable to turn on the light emitting unit when the second determination value is lower than the determination value.
(6) In the camera with a projector according to claim 4 or 5, it is preferable that the control means increases the amount of light of the light-emitting section that is lit so that the brightness is insufficient.
(7) The camera with a projector according to any one of claims 4 to 6 may further include a display unit. In this case, it is preferable that the control means displays on the display means that the light emitting unit is turned on or blinked when the brightness is lower than the first determination value.
(8) In the camera with a projector according to claim 7, it is preferable that the control unit turns on or blinks the light emitting unit when receiving the operation signal from the operation member in a state of being displayed on the display unit.
(9) In the camera with a projector according to any one of claims 1 to 8, the brightness detection unit detects brightness by calculating a ratio of pixels having a pixel signal level equal to or lower than a predetermined value. Is preferred.

  In the camera with a projector according to the present invention, when the lighting unit is controlled to be lighted according to the brightness, it can be appropriately controlled regardless of whether the light emitting unit is lit.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of an electronic camera with a built-in projector (hereinafter referred to as a camera with a PJ) according to an embodiment of the present invention. In FIG. 1, the camera with PJ has a camera unit 100, a projection unit 200, and a main body 10. Each of the camera unit 100 and the projection unit 200 is rotatably supported with respect to the main body 10 by a rotation mechanism (not shown). When the camera unit 100 is rotated about the rotation axis Q, the optical axis C of the imaging optical system 121 is rotated in the arrow direction, and when the projection unit 200 is rotated about the rotation axis Q, The optical axis P of the projection optical system 221 rotates in the direction of the arrow. A camera release switch 103 </ b> A and a liquid crystal monitor 105 (FIG. 3) to be described later are provided on the main body 10.

  The camera with a PJ illuminates a projection mode in which a camera unit 100 captures a subject image, a projection mode in which projection information such as an image is projected onto a screen or the like by a projection unit 200 (projector), and projection light from the projection unit 200 A light mode used as light is provided as an operation mode.

  FIG. 2 is a block diagram illustrating the configuration of the camera with PJ. In FIG. 2, the camera with PJ includes a projection unit 200, a camera unit 100, a CPU 101, a memory 102, an operation member 103, a liquid crystal monitor 105, and an external interface (I / F) circuit 104, and is detachable. A memory card 150 is mounted.

  The CPU 101 performs a predetermined calculation using a signal input from each part in the camera based on the control program, and sends a control signal to each part in the camera, thereby performing a photographing operation and a projection operation of the camera with PJ. To control each. The control program is stored in a nonvolatile memory (not shown) in the CPU 101.

  The memory 102 is used as a working memory for the CPU 101. The operation member 103 includes a release button 103A and the like, and sends an operation signal corresponding to the operated button or switch to the CPU 101. The memory card 150 is configured by a nonvolatile memory, and data can be written, stored, and read according to instructions from the CPU 101.

  The liquid crystal monitor 105 displays information such as images and texts according to instructions from the CPU 101. The text information includes an operation menu and a message for the camera with PJ. The external interface circuit 104 transmits / receives commands and data to / from an external device (personal computer, cradle, etc.) via a cable (not shown) or a wireless communication unit according to an instruction from the CPU 101.

  The camera unit 100 includes an image pickup optical system 121, an image pickup element 122, and an image pickup control circuit 123, and performs shooting according to an instruction from the CPU 101. The imaging optical system 121 forms a subject image on the imaging surface of the imaging element 122. As the image sensor 122, a CCD, a CMOS image sensor, or the like is used. The imaging control circuit 123 controls driving of the imaging element 122 according to an instruction from the CPU 101 and performs predetermined signal processing on an image signal output from the imaging element 122. The image data after the signal processing is recorded in the memory card 150 as an image file in a predetermined format.

  The projection unit 200 includes a projection optical system 221, a liquid crystal panel 222, an LED light source 223, and a projection control circuit 224. The LED light source 223 illuminates the liquid crystal panel 222 with brightness according to the supply current. The liquid crystal panel 222 constitutes a modulation element, and generates a light image (modulates illumination light) in accordance with a drive signal from the projection control circuit 224. The projection optical system 221 projects the modulated light emitted from the liquid crystal panel 222. The projection control circuit 224 sends a control signal to the LED light source 223 and the liquid crystal panel 222 according to an instruction from the CPU 101.

  The projection unit 200 is configured to be able to project a reproduction image based on image data supplied from an external device via the external interface circuit 104 in addition to image data stored in the memory card 150, and an image instructed by the CPU 101. Project. In the light mode described above, projection light is emitted as illumination light. The liquid crystal panel 222 in the light mode generates a white image according to an instruction from the CPU 101. When the liquid crystal panel 222 is a transmissive liquid crystal, the white image is generated by increasing the transmissivity of each pixel. When the liquid crystal panel 222 is a reflective liquid crystal, the white image is generated by increasing the reflectance of each pixel. Note that a specific color light such as red or blue may be emitted instead of the white image in the light mode.

  Since this embodiment is characterized by the operation in the write mode, this operation will be mainly described. When the CPU 101 is set to the light mode by operating the menu switch 103B, the cross switch 103D, and the determination switch 103E illustrated in FIG. 3, the CPU 101 activates the program of the flowchart illustrated in FIG.

  In step S1 of FIG. 4, the CPU 101 determines whether automatic lighting is permitted. In the automatic lighting, the illumination light is automatically turned on when it is determined that the camera is dark. Whether or not automatic lighting is possible is set in advance by a menu operation. If automatic lighting is permitted, CPU 101 makes an affirmative determination in step S1 and proceeds to step S2. If automatic lighting is not permitted, CPU 101 makes a negative determination in step S1 and proceeds to step S10.

  In step S2, the CPU 101 sends an instruction to the imaging control circuit 123, causes the camera unit 100 to start through image shooting, and proceeds to step S3. Through image shooting is to acquire subject information in real time by causing the image sensor 122 to repeatedly perform image capturing operations at predetermined intervals. The through image shooting rate in the light mode is made slower (for example, 1 frame / 3 seconds) than the through image shooting rate in the shooting mode (30 frames / second).

  FIG. 5 is a diagram illustrating a through image shooting range 52 and an illumination range 51 by the projection unit 200 in the light mode. In the light mode, the zoom lens (not shown) constituting the imaging optical system 121 is moved to the wide-angle side, so that the illumination range 51 is included in the shooting field angle. Thereby, even if the projection unit 200 emits projection light, it is possible to determine low luminance using a pixel signal that receives subject light from outside the illumination range 51.

  In step S3, the CPU 101 determines whether or not the brightness is low. The CPU 101 makes an affirmative decision in step S3 when the ratio of the signals of the predetermined signal level a or less to the pixel signals constituting the through image is B or more, and proceeds to step S4. If the ratio of signals below the predetermined signal level a is less than B, the CPU 101 makes a negative determination in step S3 and proceeds to step S8.

  In step S4, the CPU 101 determines whether the LED is on. If the LED light source 223 has already been turned on, the CPU 101 makes a positive determination in step S4 and proceeds to step S7. If the LED light source 223 has not been turned on, the CPU 101 makes a negative determination in step S4 and proceeds to step S5.

  In step S5, the CPU 101 sends an instruction to the projection control circuit 224 to drive the liquid crystal panel 222 in white, and proceeds to step S6. White driving corresponds to the above-described white image generation. In step S6, the CPU 101 sends an instruction to the projection control circuit 224, turns on the LED light source 223, and proceeds to step S7. Thereby, the projection unit 200 emits illumination light automatically.

  In step S7, the CPU 101 determines whether or not a mode change operation has been performed. When the operation of switching to the shooting mode or the projection mode is performed by the menu operation by the menu switch 103B, the cross switch 103D, and the determination switch 103E, the CPU 101 makes an affirmative determination in step S7 and ends the process of FIG. If the menu operation for switching to another mode is not performed, the CPU 101 makes a negative determination in step S7 and returns to step S1.

  In step S8, which proceeds after making a negative determination in step S3, the CPU 101 determines whether the LED is on. If the LED light source 223 has already been turned on, the CPU 101 makes a positive determination in step S8 and proceeds to step S9. If the LED light source 223 has not been turned on, the CPU 101 makes a negative determination in step S8 and proceeds to step S7.

  In step S9, the CPU 101 sends an instruction to the projection control circuit 224, turns off the LED light source 223, and proceeds to step S7. As a result, the projection unit 200 automatically stops light emission.

  In step S10, which proceeds after making a negative determination in step S1, the CPU 101 sends an instruction to the imaging control circuit 123, stops the camera unit 100 from photographing through images, and then proceeds to step S11. In step S11, the CPU 101 determines whether or not a lighting operation has been performed. When the operation signal is input from the switch 103C while the LED light source 223 is turned off, the CPU 101 makes an affirmative decision in step S11 and proceeds to step S12. When the operation signal is not input from the switch 103C while the LED light source 223 is turned off. Makes a negative determination in step S11 and proceeds to step S13. In the light mode, the switch 103C functions as an illumination light on / off switch.

  In step S12, the CPU 101 sends an instruction to the projection control circuit 224, turns on the LED light source 223, and proceeds to step S7. Note that white driving for the liquid crystal panel 222 is also performed. Thereby, the projection unit 200 emits illumination light according to the lighting operation.

  In step S <b> 13, the CPU 101 determines whether a turn-off operation has been performed. The CPU 101 makes an affirmative decision in step S13 when an operation signal is input from the switch 103C while the LED light source 223 is lit, and proceeds to step S14. If an operation signal is not input from the switch 103C, the CPU 101 makes a negative determination in step S13. The process proceeds to step S7. In step S14, the CPU 101 sends an instruction to the projection control circuit 224, turns off the LED light source 223, and proceeds to step S7. Thereby, the projection unit 200 stops the emission of illumination light in response to the turn-off operation.

  In the light mode described above, the display of the normal liquid crystal monitor 105 is normally turned off to reduce power consumption.

According to the embodiment described above, the following operational effects can be obtained.
(1) Since the light mode using the light from the LED light source 223 of the projection unit 200 as illumination light is provided, the camera with PJ can be used as a portable lamp.

(2) Since the white image is formed on the liquid crystal panel 222 in the light mode (step S5), the illumination efficiency of the light from the LED light source 223 is increased and bright illumination light is obtained.

(3) Since the LED light source 223 is automatically turned on in a low-brightness state where the brightness is insufficient (step S6), it is suitable for use situations where the user's hand is blocked and the lighting operation cannot be performed. Further, since the light is automatically turned off when it becomes brighter than the predetermined luminance (step S9), it is possible to prevent forgetting to turn it off in a bright environment.

(4) Since the low-brightness determination is performed using the live view image captured by the camera unit 100, it is not necessary to newly provide a luminance determination sensor. Further, since the low luminance determination is performed according to the ratio of each pixel signal constituting the through image having a low signal level, even if a part of the through image shooting range 52 is bright, the through image is dark. If the area is included, the LED light source 223 can be turned on.

(5) Since the through image shooting rate in the light mode is slower than the through image shooting rate in the shooting mode, it is possible to reduce power consumption as compared with the case of shooting a through image at a high rate.

(6) In the light mode, the zoom lens (not shown) constituting the imaging optical system 121 is moved to the wide-angle side, so that the through image shooting range 52 can include the illumination range 51 by the projection unit 200. Thereby, it is possible to determine low luminance using a pixel signal corresponding to a portion of the through image capturing range 52 that is not illuminated by the projection unit 200 (outside the illumination range 51).

(7) Since the camera unit 100 and the projection unit 200 are configured to be rotatable about the rotation axis Q, the through image shooting direction C and the illumination direction P can be intentionally varied. For example, when the through image shooting direction C and the illumination direction P are substantially the same, when a camera with a PJ is illuminated by a headlight of an opposite vehicle or the like, the entire area of the through image shooting range 52 becomes high in brightness. The attached camera may turn off the LED light source 223 automatically. In such a situation, if only the camera unit 100 is rotated so that the headlight light does not enter the imaging optical system 121, the LED light source 223 can be turned on without being turned off. Since the illumination direction P by the projection unit 200 may remain facing the vehicle side that emits the headlight light, the presence of the camera (user) with PJ can be notified to the vehicle side.

(Modification 1)
In step S7, the shooting mode may be entered even when the menu operation for switching to the shooting mode is not performed. In this case, when an operation signal is input from the release switch 103A in the light mode, the CPU 101 turns off the LED light source 223 and shifts to the photographing mode. Since it is possible to immediately shift to the shooting mode without operating the menu, it is possible to prevent a sudden shooting opportunity from being missed. In this case, when a predetermined time elapses without any operation in the shifted shooting mode, it is preferable to end the shooting mode, start the process of FIG. 4 again, and return to the light mode.

(Modification 2)
When the LED light source 223 is automatically turned on in the low luminance state (step S6), a message may be displayed on the liquid crystal monitor 105 before the lighting. For example, as illustrated in FIG. 3, a message “Do you want to turn on the light source?” Is displayed on the liquid crystal monitor 105, and the LED light source 223 is turned on when the determination switch 103E is operated with the message displayed. When the determination switch 103E is not operated, the LED light source 223 is not turned on. By adopting a configuration in which such an operation can be selected by a menu operation, it is possible to select an operation that does not cause automatic light emission immediately in a place where illumination is prohibited.

(Modification 3)
In addition to the second modification, an electronic sound may be emitted to prompt the user to make an instruction when the determination switch 103E is not operated for a predetermined time (for example, 10 seconds) in a state where a message is displayed. In this case, if the decision switch 103E is not operated until a predetermined time (for example, 5 seconds) has elapsed since the electronic sound was emitted, the message display on the liquid crystal monitor 105 is stopped.

(Modification 4)
The amount of light emitted when the LED light source 223 emits light may be changed according to the detected luminance. As described above, the luminance detection is performed using a through image captured image by the camera unit 100. When the LED light source 223 is lit, the current supplied to the LED light source 223 is increased as the detection luminance is lower, and the light is emitted brighter. The current supplied to the LED light source 223 is decreased as the detection luminance is higher.

(Modification 5)
The LED light source 223 may be controlled to be intermittently lit. In this case, the CPU 101 turns off the LED light source 223 when the detected luminance is higher than the first threshold, and intermittently lights (flashes) the LED light source 223 when the detected luminance falls below the first threshold, and the detected luminance is lower than the first threshold. If it falls below the low second threshold, the LED light source 223 is turned on. Since intermittent lighting consumes less power than constant lighting, a battery (not shown) can last longer than that of constant lighting.

(Modification 6)
Although an example in which the LED light source 223 of the projection unit 200 is used as illumination light has been described, an AF (autofocus) auxiliary light source, a self-timer operation display light source, or a photographing auxiliary light source may be used as illumination light.

(Modification 7)
Instead of performing low brightness determination using a through image captured image by the camera unit 100, low brightness determination may be performed using a still image captured image by the camera unit 100.

  The above description is merely an example, and is not limited to the configuration of the above-described embodiment, and may be appropriately combined with the contents of each modification.

It is a perspective view of a camera with a PJ according to an embodiment of the present invention. It is a block diagram explaining the structure of a camera with PJ. It is a figure which illustrates the operation member and liquid crystal monitor of a camera with PJ. It is a flowchart explaining the flow of the process in light mode. It is a figure which illustrates the through image photography range and illumination range at the time of light mode.

Explanation of symbols

100 ... Camera unit 101 ... CPU
DESCRIPTION OF SYMBOLS 103 ... Operation member 105 ... Liquid crystal monitor 121 ... Imaging optical system 122 ... Imaging element 200 ... Projection unit 221 ... Projection optical system 222 ... Liquid crystal panel 223 ... LED light source 224 ... Projection control circuit

Claims (9)

A projection unit that illuminates the modulation element with a light emitting unit and projects an optical image;
An imaging unit that captures a subject image and outputs an image signal;
Brightness detection means for detecting brightness using the image signal;
Control means for controlling lighting of the light emitting unit according to the brightness detected by the brightness detection means using an image signal obtained by imaging the imaging unit in a wider range than the projection range of the projection unit. Camera with projector. The camera with a projector according to claim 1,
The camera with a projector, wherein the image pickup unit repeatedly picks up an image over a wider range than a projection range by the projection unit at a predetermined interval. The camera with a projector according to claim 1 or 2,
The projector-equipped camera, wherein the projection unit controls the modulation of the modulation element so as to increase a projection light level. In the camera with a projector as described in any one of Claims 1-3,
The camera with a projector characterized in that the control means turns on the light emitting unit when the brightness is lower than a first determination value. In the camera with a projector as described in any one of Claims 1-3,
The control means blinks the light emitting unit when the brightness is less than the first determination value, and turns on the light emitting unit when the brightness is less than the second determination value lower than the first determination value. A projector-equipped camera. The camera with a projector according to claim 4 or 5,
The camera with a projector, characterized in that the control means increases the light amount of the light-emitting unit that is lit so that the brightness is insufficient. In the camera with a projector as described in any one of Claims 4-6,
A display means,
The camera with a projector, wherein when the brightness is less than a first determination value, the control means displays on the display means that the light emitting unit is turned on or blinks. The camera with a projector according to claim 7,
The camera with a projector, wherein the control unit turns on or blinks the light emitting unit when receiving an operation signal from an operation member in the state displayed on the display unit. In the camera with a projector as described in any one of Claims 1-8,
The camera with a projector, wherein the brightness detection means detects the brightness by calculating a ratio of pixels having a pixel signal level equal to or lower than a predetermined value.

Images