JP2012118399A - Image display device and portable information processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable laser light to be protected from being projected in an unnecessary direction when a device is moved by impact.SOLUTION: When detecting impact applied to a device based on an output of an acceleration sensor 95, the output of laser light by an optical engine section is stopped. In particular, the acceleration sensor is a tri-axial acceleration sensor capable of detecting accelerations in three directions at right angles to one another and performs to: detect a presence of the impact based on the acceleration in a second direction along a rotational axis of a hinge section 73 which rotates an optical engine unit 13 in a direction vertically changing a projection angle; obtain the projection angle based on the accelerations in the remaining two directions; and correct a trapezoidal distortion of a screen in accordance with the projection angle.

Description

  The present invention relates to an image display device that projects a screen onto a screen with laser light, and more particularly to an image display device that is suitable for being incorporated in a portable electronic device.

  In recent years, a technique using a semiconductor laser as a light source of an image display device has attracted attention. This semiconductor laser has better color reproducibility, instantaneous lighting, longer life, and higher power consumption compared to mercury lamps that have been widely used in image display devices. It has various advantages, such as being able to be made and being easy to miniaturize.

  The advantage of such an image display device using a semiconductor laser is convenient when it is built in a portable electronic device. For example, a technique for incorporating an image display device using a semiconductor laser into a mobile phone terminal is known. (See Patent Document 1). When the image display device is built in the portable electronic device in this way, the screen can be enlarged and displayed on the screen as needed, so that convenience can be improved.

JP 2007-316393 A

  Now, in an image display device using a semiconductor laser as a light source, it is necessary to urge the user to pay attention to handling because the laser beam is damaged when it enters the human eye for a long time. In the configuration in which the image display device is built in the portable electronic device, the weight of the device is small, and the device may move easily even if a light impact is applied by hitting the user's body. It is conceivable that the laser light enters the human eye for a short time due to a large change in the light projection direction, and it is desirable to avoid such a situation.

  The present invention has been devised to solve such problems of the prior art, and its main purpose is to project a laser beam in a useless direction when the apparatus moves due to an impact. An object of the present invention is to provide an image display device configured to prevent the occurrence of the above problem.

  An image display device of the present invention includes an optical engine unit that projects a screen onto a screen by laser light, a control unit that controls the optical engine unit, and an acceleration sensor that detects acceleration generated in the device, and the control The unit is configured to stop the output of the laser beam from the optical engine unit when detecting an impact applied to the apparatus based on the output of the acceleration sensor.

  According to the present invention, when an impact is applied to the apparatus, the output of the laser beam by the optical engine unit is stopped, so that it is possible to prevent the laser beam from being projected in an unnecessary direction.

The perspective view which shows the example which incorporated the image display apparatus 1 by this invention in the portable information processing apparatus 2 Schematic configuration diagram of an optical engine unit 21 built in the optical engine unit 13 The schematic diagram which shows the condition of the laser beam in the green laser light source device 22 The perspective view which shows the image display apparatus 1 The block diagram which shows schematic structure of the image display apparatus 1 The figure which shows the image display apparatus 1 and the portable information processing apparatus 2 Side view showing the situation where the screen is projected diagonally upward with respect to the screen The figure which shows the output screen of the image display apparatus 1, and the screen on a screen Diagram showing the relationship between the projection angle θ and the correction coefficient A top view showing a situation where the image display device 1 is turned off in response to an impact applied while the image display device 1 is turned on.

  A first invention made to solve the above-described problems is an optical engine unit that projects a screen onto a screen by laser light, a control unit that controls the optical engine unit, and an acceleration sensor that detects acceleration generated in the apparatus. The control unit is configured to stop the output of the laser beam from the optical engine unit when detecting an impact applied to the apparatus based on the output of the acceleration sensor.

  According to this, when an impact is applied to the apparatus, the output of the laser beam by the optical engine unit is stopped, so that it is possible to prevent the laser beam from being projected in an unnecessary direction.

  In addition, a second aspect of the present invention includes at least a projection optical system constituting the optical engine unit according to the first aspect of the invention, and is rotatable on the main body side via a hinge part in a direction to change the projection angle in the vertical direction. The acceleration sensor is a three-axis acceleration sensor capable of detecting acceleration in three directions orthogonal to each other, a first direction along the optical axis of the projection light, and the hinge unit Is arranged in the projection unit so as to detect acceleration in a second direction along the rotation axis of the first direction and a third direction orthogonal to both the first direction and the second direction, and the control unit The projection angle is obtained based on the acceleration in the first direction and the third direction detected by the acceleration sensor, and the trapezoidal distortion of the screen is corrected according to the projection angle, and is detected by the acceleration sensor. Constitute the determines the presence or absence of an impact based on the second direction of the acceleration.

  According to this, since the acceleration sensor is used for both the projection angle detection and the impact detection, only one acceleration sensor is required, and the manufacturing cost can be reduced.

  In this case, the acceleration sensor detects the gravitational acceleration components in the first direction and the third direction, whereby the projection angle can be obtained. Also, the image display device is usually used by being placed on a horizontal desk or the like, and when an impact is applied to the device, the device moves along the placement surface. On the other hand, since the projection angle is changed in the vertical direction, the rotation axis of the hinge portion is in the horizontal direction, and the second direction is a direction along the horizontal placement surface. For this reason, even if it is the structure which detects an impact only with the acceleration of a 2nd direction, practically sufficient detection accuracy can be ensured.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the image display device is built in a portable electronic device, and includes at least a projection optical system constituting the optical engine unit. However, it is set as the structure provided so that withdrawing | inserting with respect to the housing | casing of the said electronic device was possible.

  According to this, since the portable electronic device is relatively light and easy to move, and the projection unit protrudes from the electronic device, it is easy to hit an object such as a user's body. is there.

  In a fourth aspect based on the third aspect, the electronic device is a portable information processing device, and an optical disk device can be replaced in an accommodation space formed in the casing of the portable information processing device. It is set as the structure which was accommodated in.

  According to this, the convenience of the portable information processing apparatus can be improved. Here, the optical disc apparatus performs at least one of recording and reproduction of information on an optical disc such as a Blu-ray disc, a DVD, and a CD.

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

  FIG. 1 is a perspective view showing an example in which an image display device 1 according to the present invention is built in a portable information processing device 2. The portable information processing device (electronic device) 2 includes a main body 3 in which a control board (not shown) on which a CPU, a memory, and the like are mounted, and a display unit 4 that includes a liquid crystal panel. The main body unit 3 and the display unit 4 are connected by a hinge unit 5 so that the main body unit 3 and the display unit 4 are overlapped to enhance portability.

  A keyboard 6 and a touch pad 7 are provided on the upper surface 8 a of the housing 8 of the main body 3. In addition, on the back surface side of the keyboard 6 in the housing 8 of the main body 3, an accommodation space in which a peripheral device such as an optical disk device is accommodated in a replaceable manner, a so-called drive bay, is formed. 1 is attached.

  The image display device 1 includes a housing 11 and a movable body 12 provided so as to be able to be taken in and out of the housing 11. The movable body 12 accommodates an optical engine unit (projection unit) 13 in which optical components for projecting the screen 16 onto the screen 15 are accommodated, and a substrate for controlling the optical components in the optical engine unit 13. And a control unit (support unit) 14.

  FIG. 2 is a schematic configuration diagram of the optical engine unit 21 built in the optical engine unit 13. The optical engine unit 21 includes a green laser light source device 22 that outputs green laser light, a red laser light source device 23 that outputs red laser light, a blue laser light source device 24 that outputs blue laser light, and a video signal. The liquid crystal reflection type light modulation element 25 that modulates the laser light from each of the laser light source devices 22 to 24, and the laser light from each of the laser light source devices 22 to 24 is reflected and irradiated to the light modulation element 25. A polarization beam splitter 26 that transmits the modulated laser light emitted from the modulation element 25, a relay optical system 27 that guides the laser light emitted from each of the laser light source devices 22 to 24 to the polarization beam splitter 26, and the polarization beam splitter 26 are provided. And a projection optical system 28 that projects the transmitted modulated laser light onto a screen.

  The optical engine unit 21 displays a color image by a so-called field sequential method. Laser beams of each color are sequentially output from the laser light source devices 22 to 24 in a time-sharing manner, and an image by the laser beam of each color is visually displayed. It is recognized as a color image by the afterimage effect.

  The relay optical system 27 includes collimator lenses 31 to 33 that convert the laser beams of the respective colors emitted from the laser light source devices 22 to 24 into parallel beams, and the laser beams of the respective colors that have passed through the collimator lenses 31 to 33 in a predetermined direction. First and second dichroic mirrors 34 and 35 guided to, a diffusion plate 36 for diffusing the laser light guided by the dichroic mirrors 34 and 35, and a field lens for converting the laser light that has passed through the diffusion plate 36 into a convergent laser 37.

  If the side from which the laser light is emitted from the projection optical system 28 toward the screen is the front side, the blue laser light is emitted backward from the blue laser light source device 24, and the green laser is emitted with respect to the optical axis of the blue laser light. The green laser light and the red laser light are emitted from the green laser light source device 22 and the red laser light source device 23 so that the optical axis of the light and the optical axis of the red laser light are orthogonal to each other. And the green laser light are guided to the same optical path by the two dichroic mirrors 34 and 35. That is, the blue laser light and the green laser light are guided to the same optical path by the first dichroic mirror 34, and the blue laser light, the green laser light, and the red laser light are guided to the same optical path by the second dichroic mirror 35.

  The first and second dichroic mirrors 34 and 35 are formed with films for transmitting and reflecting laser light of a predetermined wavelength on the surface, and the first dichroic mirror 34 transmits blue laser light. And reflects the green laser light. The second dichroic mirror 35 transmits red laser light and reflects blue laser light and green laser light.

  Each of these optical members is supported by the housing 41. The housing 41 functions as a radiator that dissipates heat generated by the laser light source devices 22 to 24, and is formed of a material having high thermal conductivity such as aluminum or copper.

  The green laser light source device 22 is attached to an attachment portion 42 formed on the housing 41 in a state of protruding toward the side. The attachment portion 42 is provided in a state of protruding in a direction perpendicular to the side wall portion 44 from a corner portion where the front wall portion 43 and the side wall portion 44 that are respectively positioned in front and side of the accommodation space of the relay optical system 27 intersect. ing. The red laser light source device 23 is attached to the outer surface side of the side wall 44 while being held by the holder 45. The blue laser light source device 24 is attached to the outer surface side of the front wall portion 43 while being held by the holder 46.

  The red laser light source device 23 and the blue laser light source device 24 are configured by a so-called CAN package, and the optical axis is positioned on the central axis of the can-shaped exterior portion with the laser chip that outputs the laser light supported by the stem. The laser beam is emitted from a glass window provided in the opening of the exterior part. The red laser light source device 23 and the blue laser light source device 24 are fixed to the holders 45 and 46 by, for example, press-fitting into the mounting holes 47 and 48 formed in the holders 45 and 46. The heat generated by the laser chips of the blue laser light source device 24 and the red laser light source device 23 is transmitted to the housing 41 through the holders 45 and 46 to be dissipated, and each of the holders 45 and 46 has a thermal conductivity such as aluminum or copper. It is made of a high material.

  The green laser light source device 22 includes a semiconductor laser 51 that outputs excitation laser light, a FAC (Fast-Axis Collimator) lens 52 that is a condensing lens that condenses the excitation laser light output from the semiconductor laser 51, and a rod. A lens 53, a solid-state laser element 54 that outputs a basic laser beam (infrared laser beam) when excited by an excitation laser beam, and converts a wavelength of the basic laser beam to output a half-wavelength laser beam (green laser beam) A wavelength conversion element 55, a concave mirror 56 that forms a resonator together with the solid-state laser element 54, a glass cover 57 that prevents leakage of excitation laser light and fundamental wavelength laser light, and a base 58 that supports each part, And a cover body 59 that covers each part.

  The green laser light source device 22 is fixed by attaching the base 58 to the mounting portion 42 of the housing 41, and a required width (for example, 0.5 mm) between the green laser light source device 22 and the side wall portion 44 of the housing 41. The following gaps are formed. This makes it difficult for the heat of the green laser light source device 22 to be transmitted to the red laser light source device 23, suppresses the temperature rise of the red laser light source device 23, and allows the red laser light source device 23 with poor temperature characteristics to operate stably. Can do. Further, in order to secure a required optical axis adjustment allowance (for example, about 0.3 mm) of the red laser light source device 23, a required width (for example, 0.3 mm or more) is provided between the green laser light source device 22 and the red laser light source device 23. ) Is provided.

  FIG. 3 is a schematic diagram showing the state of laser light in the green laser light source device 22. The laser chip 61 of the semiconductor laser 51 outputs excitation laser light having a wavelength of 808 nm. The FAC lens 52 reduces the spread of the first axis of the laser beam (the direction perpendicular to the optical axis direction and along the drawing sheet). The rod lens 53 reduces the spread of the slow axis of laser light (in the direction perpendicular to the drawing sheet).

The solid-state laser element 54 is a so-called solid-state laser crystal, and is excited by excitation laser light having a wavelength of 808 nm that has passed through the rod lens 53 to output fundamental wavelength laser light (infrared laser light) having a wavelength of 1064 nm. This solid-state laser element 54 is obtained by doping an inorganic optically active substance (crystal) made of Y (yttrium) VO ₄ (vanadate) with Nd (neodymium), and more specifically, YVO _{4 as} a base material. The Y is doped by substitution with Nd ⁺³ which is an element that emits fluorescence.

  On the side of the solid-state laser element 54 facing the rod lens 53, a film having a function of preventing reflection of excitation laser light having a wavelength of 808 nm and high reflection of fundamental wavelength laser light having a wavelength of 1064 nm and half-wavelength laser light having a wavelength of 532 nm. 62 is formed. On the side of the solid-state laser element 54 facing the wavelength conversion element 55, a film 63 having an antireflection function for a fundamental wavelength laser beam having a wavelength of 1064 nm and a half wavelength laser beam having a wavelength of 532 nm is formed.

  The wavelength conversion element 55 is a so-called SHG (Second Harmonics Generation) element, which converts the wavelength of a fundamental wavelength laser beam (infrared laser beam) having a wavelength of 1064 nm output from the solid-state laser element 54 to a half-wavelength laser having a wavelength of 532 nm. Light (green laser light) is generated.

  On the side of the wavelength conversion element 55 facing the solid-state laser element 54, a film 64 having functions of preventing reflection of the fundamental wavelength laser light having a wavelength of 1064 nm and highly reflecting the half wavelength laser light having a wavelength of 532 nm is formed. On the side of the wavelength conversion element 55 facing the concave mirror 56, a film 65 having an antireflection function for the fundamental wavelength laser beam having a wavelength of 1064 nm and the half wavelength laser beam having a wavelength of 532 nm is formed.

  The concave mirror 56 has a concave surface on the side facing the wavelength conversion element 55, and this concave surface has a function of high reflection with respect to a fundamental wavelength laser beam with a wavelength of 1064 nm and antireflection with respect to a half wavelength laser beam with a wavelength of 532 nm. A film 66 is formed. As a result, the fundamental wavelength laser beam having a wavelength of 1064 nm resonates and is amplified between the film 62 of the solid-state laser element 54 and the film 66 of the concave mirror 56.

  In the wavelength conversion element 55, a part of the fundamental wavelength laser light having a wavelength of 1064 nm incident from the solid-state laser element 54 is converted into a half-wavelength laser light having a wavelength of 532 nm, and the fundamental wavelength of 1064 nm that has passed through the wavelength conversion element 55 without being converted is converted. The wavelength laser beam is reflected by the concave mirror 56 and is incident on the wavelength conversion element 55 again, and is converted into a half-wavelength laser beam having a wavelength of 532 nm. The half-wavelength laser light having a wavelength of 532 nm is reflected by the film 64 of the wavelength conversion element 55 and emitted from the wavelength conversion element 55.

  Here, the laser beam B1 incident on the wavelength conversion element 55 from the solid-state laser element 54, converted in wavelength by the wavelength conversion element 55, and emitted from the wavelength conversion element 55, and once reflected by the concave mirror 56 and converted in wavelength. In the state where the laser beam B2 incident on the element 55, reflected by the film 64 and emitted from the wavelength conversion element 55 overlaps with each other, the half-wavelength laser light having a wavelength of 532 nm and the fundamental wavelength laser light having a wavelength of 1064 nm interfere with each other. Cause output to drop.

  Therefore, here, the wavelength conversion element 55 is inclined with respect to the optical axis direction so that the laser light beams B1 and B2 do not overlap each other by the refraction action on the entrance surface and the exit surface. Interference between the wavelength laser beam and the fundamental wavelength laser beam having a wavelength of 1064 nm is prevented, so that a decrease in output can be avoided.

  The glass cover 57 shown in FIG. 2 is formed with a film that does not transmit these laser beams in order to prevent the excitation laser beam having a wavelength of 808 nm and the fundamental wavelength laser beam having a wavelength of 1064 nm from leaking to the outside. ing.

  FIG. 4 is a perspective view showing the image display device 1. FIG. 4A shows a storage state in which the movable body 12 is stored in the housing 11, and FIG. 4B shows the movable body 12 in the housing. 11 shows the state of use drawn from 11 respectively.

  Each housing of the optical engine unit 13 and the control unit 14 constituting the movable body 12 has a flat box shape with a short dimension in the height direction. Sliders 71 and 72 that slide along guide rails (not shown) provided in the casing 11 are provided on both side edges of the casings of the optical engine unit 13 and the control unit 14. In operation, as indicated by an arrow A, the movable body 12 is moved in and out of the housing 11.

  The optical engine unit 13 and the control unit 14 are connected via a hinge 73, and the optical engine unit 13 is rotatably supported by the control unit 14 (member on the main body side). An exit window 74 is provided at the end of the optical engine unit 13 opposite to the hinge portion 73, and laser light that has passed through the projection optical system 28 (see FIG. 2) of the optical engine unit 21 from the exit window 74. Is emitted.

  As shown in FIG. 1, the storage space of the image display device 1 is open on the side surface of the casing 8 of the portable information processing device 2, and the side surface of the casing 8 of the portable information processing device 2 is open. The movable body 12 is taken in and out in a substantially orthogonal direction. The casing 11 of the image display device 1 is accommodated in the casing 8 of the portable information processing device 2, and in use, a part of the optical engine unit 13 and the control unit 14 is included in the casing 8 of the portable information processing device 2. It will be in the state which protruded to the side. The portable information processing device 2 is arranged so that its side faces the screen, and thus the exit window 74 provided in the optical engine unit 13 can face the screen.

  Further, the hinge portion 73 shown in FIG. 4 has an orthogonal biaxial structure. In the use state shown in FIG. 4B, the control unit 14 is supported by the guide rails of the housing 11 while the optical engine unit. 13 is completely removed from the housing 11, and the optical engine unit 13 can be rotated in the vertical direction as indicated by the arrow B. Also, as indicated by the arrow C, the front and rear direction, that is, the movable body 12 is taken in and out. The optical engine unit 13 can be rotated around the direction axis.

  An operation unit 75 is provided on the upper surface of the control unit 14, and the operation unit 75 includes a power operation button 76, a luminance switching operation button 77, and two operations for correcting trapezoidal distortion. Buttons 78 and 79 are provided. In addition, a latch lock (not shown) is provided in the housing 11 in order to hold the movable body 12 in the storage position.

  FIG. 5 is a block diagram illustrating a schematic configuration of the image display apparatus 1. The control unit 81 of the image display device 1 controls the light source control unit 82 that controls the laser light source devices 22 to 24 of each color and the light modulation element 25 based on the video signal input from the portable information processing device 2. A light modulation element control unit 83, a power supply unit 84 that supplies power supplied from the portable information processing device 2 to the laser light source control unit 82 and the light modulation element control unit 83, and a main control unit that comprehensively controls each unit. 85. The control unit 81 is provided in the control unit 14.

  In the optical engine unit 21, in addition to the laser light source devices 22 to 24 for each color and the light modulation element 25, a photosensor 86 for detecting the amount of light incident on the light modulation element 25 and a temperature in the vicinity of the light modulation element 25 are detected. A temperature sensor 87 is provided. The optical engine unit 21 is provided in the optical engine unit 13. The optical engine unit 13 is provided with a cooling fan 88 for cooling the optical engine unit 21 in addition to the optical engine unit 21.

  In order to transmit a video signal from the power supply line for supplying power from the portable information processing device 2 and the portable information processing device 2 to the casing 11 of the image display device 1 (see also FIG. 4). The interface unit 91 to which the signal line is connected is provided, and the interface unit 91 and the control unit 14 are connected by the wiring cable 92. The wiring cable 92 has flexibility and bends and deforms so as to follow the control unit 14 when the movable body 12 is taken in and out of the housing 11.

  The control unit 14 and the optical engine unit 13 are connected by a wiring cable 93. The wiring cable 93 includes a signal line for transmitting and receiving a signal between each unit in the control unit 81 and each unit in the optical engine unit 21 and a power supply line for supplying power to the cooling fan 88 and the like. . The wiring cable 93 is also flexible, and when the optical engine unit 13 is rotated with respect to the control unit 14, the wiring cable 93 is bent and deformed as the optical engine unit 13 is rotated.

  Although the control unit 81 is provided in the control unit 14 here, a part of the control unit 81, for example, the power supply unit 84, may be provided on the housing 11 side together with the interface unit 91.

  Further, an acceleration sensor 95 is provided in the optical engine unit 21 in the optical engine unit 13. The acceleration sensor 95 is used to determine the projection angle, that is, the inclination angle of the optical axis of the projection light emitted from the emission window 74 of the optical engine unit 13 with respect to the horizontal direction, as shown in FIG. It is used for the purpose of detecting the impact applied to the surface. The acceleration sensor 95 will be described in detail later.

  Further, as shown in FIG. 5, the control unit 81 includes a screen correction unit 96 that corrects trapezoidal distortion that occurs when the screen is projected in an oblique direction with respect to the screen. The screen correction unit 96 performs a scaler process (pixel conversion process) for converting a rectangular output screen into a trapezoidal shape opposite to the trapezoidal distortion generated in the projection screen on the screen by pixel thinning or interpolation. This trapezoidal distortion correction is performed based on the tilt angle obtained from the output signal of the acceleration sensor 95, which will be described in detail later.

  The main control unit 85 includes an impact detection unit 97 that detects an impact applied to the image display device 1. The output signal of the acceleration sensor 95 is input to the main control unit 85, and the impact detection unit 97 determines the presence or absence of an impact based on the output signal of the acceleration sensor 95, and determines that there is an impact here. Then, the main control unit 85 outputs a stop signal to the power supply unit 84, stops the power supply to the laser light source control unit 82 and the light modulation element control unit 83, etc., and outputs the projection light by the optical engine unit 21. To stop.

  FIG. 6 is a diagram showing the image display device 1 and the portable information processing device 2. FIG. 6A shows a state viewed from the front of the portable information processing device 2, and FIG. 6B shows portable information. The state seen from the side of processing device 2 is shown, respectively.

  As described above, the optical engine unit 13 can rotate in a direction in which the projection angle, that is, the inclination angle of the optical axis of the projection light emitted from the exit window 74 of the optical engine unit 13 with respect to the horizontal direction is changed in the vertical direction. The projection unit is supported by the control unit 14 via the hinge unit 73, and the projection angle can be adjusted by rotating the optical engine unit 21.

  The acceleration sensor 95 provided in the optical engine unit 13 is a three-axis type sensor that can detect accelerations in three directions orthogonal to each other, and is on the optical axis of the projection light emitted from the emission window 74 of the optical engine unit 13. The first direction along the second direction, the second direction along the rotation axis of the hinge 73, and the third direction orthogonal to both the first direction and the second direction are arranged to detect acceleration. Has been.

  The main control unit 85 of the control unit 81 shown in FIG. 5 calculates the projection angle θ based on the accelerations in the first direction and the third direction detected by the acceleration sensor 95, and according to the projection angle θ. The screen correction unit 96 performs processing for correcting the trapezoidal distortion of the screen. Here, when the acceleration sensor 95 is stationary, the acceleration sensor 95 detects the gravitational acceleration components in the first direction and the third direction, whereby the projection angle θ can be obtained.

  Further, the impact detection unit 97 performs processing for determining the presence or absence of an impact based on the acceleration in the second direction detected by the acceleration sensor 95.

  As shown in FIG. 6B, the image display device 1 is attached to the portable information processing device 2 while being tilted along the upper surface of the main body 3 on which the keyboard is disposed, and the optical engine unit. Reference numeral 13 is rotatable as indicated by an arrow C. By setting the optical engine unit 13 in the horizontal direction, the screen can be displayed in an appropriate state in which the vertical and horizontal directions of the screen are the horizontal and vertical directions, respectively. Displayed on the screen.

  FIG. 7 is a side view showing a situation in which the screen is projected obliquely upward with respect to the screen 15. FIG. 8 is a diagram showing an output screen of the image display device 1 and a screen on the screen 15.

  As shown in FIG. 7, when the screen is projected obliquely upward with respect to the screen 15, the distance to the screen 15 increases on the upper side of the screen. For this reason, when the rectangular output screen shown in FIG. 8A is projected onto the screen 15 as it is, the screen on the screen 15 is displayed in a trapezoidal shape with the upper side larger than the lower side, as shown in FIG. 8B. Is done. Therefore, the screen correction unit 96 performs processing for correcting the trapezoidal distortion of the screen.

  FIG. 9 is a diagram showing the relationship between the projection angle θ and the correction coefficient. The screen correction unit 96 shown in FIG. 5 performs trapezoidal distortion correction that compresses the upper side of the screen according to a correction coefficient determined according to the projection angle θ.

  Here, the correction coefficient represents the ratio between the upper side and the lower side of the projection screen displayed in a trapezoidal shape, and when the projection angle θ is 0, that is, when the screen is projected sideways, the correction coefficient is 1, and the keystone distortion No correction is made. In addition, the correction coefficient increases as the projection angle θ increases, and the correction amount of the trapezoidal distortion correction increases according to the value of the correction coefficient. Therefore, the correction coefficient becomes conspicuous as the projection angle θ increases. It is possible to appropriately correct the screen distortion.

  With this trapezoidal distortion correction, as shown in FIG. 8C, the corrected output screen has a trapezoidal shape whose upper side is smaller than the lower side, and when this is projected onto the screen 15, it is shown in FIG. 8D. Thus, a rectangular screen having the same length of the upper side and the lower side and without distortion is displayed.

  Here, the upper side of the screen is compressed in the trapezoidal distortion correction. However, the trapezoidal distortion correction method is not limited to this, and a projection screen without distortion is finally displayed on the screen. It is only necessary to correct as described above, and various known methods can be used.

  The trapezoidal distortion correction operation buttons 78 and 79 shown in FIG. 4 are used to manually adjust the trapezoidal distortion correction. For example, the projection screen obtained by trapezoidal distortion correction that is automatically performed based on the projection angle. When the distortion remains, the fine adjustment of the trapezoidal distortion correction can be performed.

  FIG. 10 is a top view illustrating a state in which the image display device 1 is turned off in response to an impact applied while the image display device 1 is turned on.

  As shown in FIG. 6, the image display device 1 is normally used by being placed on a horizontal placement surface 101 such as a table top, and projection is performed by horizontally arranging the rotation shaft of the hinge portion 73. Of the three directions in which the angle can be changed in the vertical direction and the acceleration is detected by the acceleration sensor 95, the second direction used for impact detection is a direction along the horizontal mounting surface 101. Become.

  On the other hand, as shown in FIG. 10A, when an impact force is applied to the image display device 1 or the portable information processing device 2 by hitting the user's body, as shown in FIG. The information processing apparatus 2 moves along the placement surface 101. At this time, since acceleration in the second direction is generated in the acceleration sensor 95 provided in the optical engine unit 13, the impact detection unit 97 detects the impact and turns off the light, that is, the output of the laser light is stopped. Accordingly, it is possible to prevent the laser light from being projected in an unnecessary direction and reliably avoid the laser light from entering the human eye.

  Here, only the acceleration in the second direction detected by the acceleration sensor 95 is used for impact detection. For this reason, when an impact force acts in a direction orthogonal to the second direction, the impact cannot be detected. For example, when an impact is applied to the optical engine unit 13 in the vertical direction, the optical engine unit 13 rotates and the projection direction changes greatly in the vertical direction. In this case, the impact cannot be detected. However, there is a possibility that there is a person on the side of the screen, but it is unlikely that a person is below or above the screen, and even if the projection direction changes greatly up and down, the laser light can enter the human eye There is almost no sex. For this reason, there is no practical problem even if the impact in the vertical direction cannot be detected.

  By the way, the image display apparatus 1 can adjust the projection angle in the vertical direction by rotating the optical engine unit 13, but cannot adjust the projection direction to the left and right. For this reason, it is necessary to adjust the projection direction by moving the portable information processing device 2 while looking at the screen on the screen. At this time, the acceleration sensor 95 generates acceleration in the second direction. There is a risk of erroneous determination that something has been added.

  Therefore, it is desirable to distinguish between a movement operation for position adjustment and an impact, and to turn off the light only when the impact is applied. For this purpose, it is preferable to adopt a configuration in which it is determined that there is an impact when the absolute value of the output value of the acceleration sensor 95 exceeds a predetermined threshold value, focusing on the fact that the magnitude of the acceleration differs between the moving operation and the impact.

  Further, in order to suppress false detection caused by noise or the like, the absolute value of the output value of the acceleration sensor 95 is integrated within a predetermined determination period, and there is an impact when the integrated value exceeds a predetermined threshold value. It is good also as a structure to determine. Also, focusing on the fact that the temporal change state of acceleration differs between the moving operation and the impact, a configuration for determining that there is an impact when the temporal change pattern of the output value of the acceleration sensor 95 matches a predetermined pattern It is good. In addition, each of these determination criteria may be used alone, or may be combined appropriately to perform impact detection.

  The acceleration sensor 95 also detects the acceleration when the optical engine unit 13 is rotated to adjust the projection angle. However, since the acceleration in this direction is not used for impact detection, the optical engine The projection angle adjustment operation by the rotation of the unit 13 is not erroneously detected as an impact.

  Here, the example in which the image display device 1 according to the present invention is built in the portable information processing device 2 is shown, but it can also be built in an electronic device such as another portable information terminal device. Since the portable electronic device is relatively light and easy to move, and the optical engine unit 13 of the image display device 1 protrudes from the electronic device. It is valid.

  In the above example, the image display device 1 according to the present invention is accommodated in the accommodation space of the portable information processing device 2 so as to be replaceable with the optical disc device. A configuration is also possible in which the device is housed in a state where it cannot be replaced with another device such as an optical disk device.

  Further, in the above example, the projection unit that is rotatably provided to change the projection angle in the vertical direction is the optical engine unit that accommodates the entire optical engine unit. However, the projection unit in the present invention is an optical unit. Any configuration that includes at least a projection optical system that is a part of the engine unit may be used. For example, a configuration in which the projection angle is changed by a mirror that configures the projection optical system is also possible.

  The image display device according to the present invention has an effect of preventing the laser light from being projected in an unnecessary direction when the device moves due to an impact, and the screen is displayed on the screen by the laser light. It is useful as an image display device for projection.

1 Image display device 2 Portable information processing device (electronic equipment)
12 Movable body 13 Optical engine unit (projection unit)
14 Control unit 21 Optical engine part 73 Hinge part 74 Outgoing window 81 Control part 95 Acceleration sensor 96 Screen correction part 97 Impact detection part

The present invention relates to an image display device and a portable information processing device that project a screen onto a screen with laser light.

The present invention has been devised to solve such problems of the prior art, and its main purpose is to project a laser beam in a useless direction when the apparatus moves due to an impact. An object of the present invention is to provide an image display device and a portable information processing device that are configured to prevent such a situation.

The image display device of the present invention includes at least a projection optical system that constitutes an optical engine unit that projects a screen onto a screen by laser light, and is rotatable through a hinge unit in a direction in which the projection angle is changed in the vertical direction. and a projection unit supported by the member on the main body side, and a control unit which controls the optical engine unit, disposed in the projection unit, a first direction along the optical axis of the projection light, rotation axis of the hinge portion And an acceleration sensor that detects acceleration in a third direction orthogonal to both the first direction and the second direction, and the control unit is detected by the acceleration sensor. A projection angle is obtained based on the accelerations in the first direction and the third direction, the trapezoidal distortion of the screen is corrected according to the projection angle, and the second direction detected by the acceleration sensor is added. To determine the presence or absence of impact applied to the apparatus main body based on a time, when it is determined that there is an impact, a configuration for stopping the output of the laser light by the optical engine unit.

According to the present invention, since the acceleration sensor is used for both the projection angle detection and the impact detection, only one acceleration sensor is required, the manufacturing cost can be reduced, and the impact on the apparatus is detected. Then, since the output of the laser beam by the optical engine unit is stopped, it is possible to prevent the laser beam from being projected in an unnecessary direction.

A first invention made to solve the above-described problems includes at least a projection optical system that constitutes an optical engine unit that projects a screen onto a screen by laser light, and the hinge unit is arranged to change the projection angle in the vertical direction. and a projection unit supported by the member on the main body side rotatably via a control unit which controls the optical engine unit, disposed in the projection unit, a first direction along the optical axis of the projection light, An acceleration sensor that detects acceleration in a second direction along the rotation axis of the hinge portion and a third direction orthogonal to both the first direction and the second direction; and the control unit biopsy, seeking projection angle on the basis of the acceleration of the first direction and the third direction detected by the acceleration sensor, as well as correcting the keystone distortion of the screen according to the projection angle by the acceleration sensor It is to determine the presence or absence of impact applied to the apparatus main body based on the acceleration in the second direction, when it is determined that there is an impact, a configuration for stopping the output of the laser light by the optical engine unit.

According to this, to shared acceleration sensor on a projection angle detection applications and shock sensing applications, the acceleration sensor requires only one, it is possible to reduce the manufacturing costs, moreover, an impact to the device Ru is detected Since the output of the laser beam by the optical engine unit is stopped, it is possible to prevent the laser beam from being projected in an unnecessary direction.

A second invention is a portable information processing device incorporating the image display device of the first invention , wherein the projection unit including at least a projection optical system constituting the optical engine unit is an apparatus main body. A configuration is provided so that the housing can be taken in and out.

According to this, the portable information processing apparatus easy to move relatively lightweight, particularly since the projection unit and protrudes from the main body, it becomes easy to hit things, such as a user's body, useless direction of the laser beam projection prevention to is that to function effectively.

According to a third aspect of the present invention, in the second aspect of the present invention, the image display device is accommodated in an accommodation space formed in the housing of the apparatus main body so as to be replaceable with an optical disk device.

Claims (4)

An optical engine that projects a screen onto the screen by laser light;
A control unit for controlling the optical engine unit;
An acceleration sensor for detecting acceleration generated in the device,
The control unit stops output of laser light from the optical engine unit when detecting an impact applied to the device based on an output of the acceleration sensor. At least a projection optical system constituting the optical engine unit, and a projection unit supported by a member on the main body side so as to be rotatable through a hinge unit in a direction to change the projection angle in the vertical direction;
The acceleration sensor is a triaxial acceleration sensor capable of detecting acceleration in three directions orthogonal to each other, and includes a first direction along the optical axis of the projection light and a second direction along the rotation axis of the hinge portion. , Arranged in the projection unit to detect acceleration in a third direction orthogonal to both the first direction and the second direction,
The control unit obtains a projection angle based on the accelerations in the first direction and the third direction detected by the acceleration sensor, corrects a trapezoidal distortion of the screen according to the projection angle, and the acceleration sensor. The image display device according to claim 1, wherein the presence or absence of an impact is determined based on the acceleration in the second direction detected by the step. An image display device built in a portable electronic device,
3. The image display according to claim 1, wherein a projection unit including at least a projection optical system constituting the optical engine unit is provided so as to be able to be inserted into and removed from a casing of the electronic device. apparatus.   4. The electronic device is a portable information processing device, and is accommodated in an accommodation space formed in a casing of the portable information processing device so as to be replaceable with an optical disk device. The image display device described in 1.

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