JP2005354398A - Mobile information terminal unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile information terminal unit which can equally irradiate a subject with a simple arrangement upon imaging. <P>SOLUTION: A mobile information terminal unit is provided with a lighting unit 19 irradiating the imaging region Ac of a camera unit 18, and a fly eye lens 57. Light entering each lens 58 of the fly eye lens 57 from an LED 50a through a collimator 56 is superimposed in a specified light irradiation region Al including the imaging region Ac of the camera unit 18. Thus, by a simple arrangement without providing a plurality of light sources to a mobile telephone unit, the light from the LED 50a can be equality irradiated to the imaging region of the subject. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a portable information terminal such as a mobile phone or a portable personal computer, and more particularly to a portable information terminal including a camera capable of capturing an image of a subject such as an operator or a surrounding object or a landscape.

  2. Description of the Related Art In recent years, in portable information terminals such as mobile phones and portable personal computers, a camera using an image sensor has been developed along with an increase in data transfer speed due to development of a wireless communication system such as wideband code division access (W-CDMA). Those equipped with (so-called mobile cameras) are widely used.

In this type of portable information terminal, as a technique for irradiating a subject with uniform illumination light during imaging, for example, there is a technique disclosed in Patent Document 1. In this technique, a plurality of light emitting diodes (LEDs) are annularly arranged around a lens of a camera, and illumination light emitted from each LED is superimposed on the subject surface to irradiate the subject without any spots.
JP 2003-259182 A

  However, since the technique described in Patent Document 1 uses a plurality of LEDs as a light source, the structure is complicated, and is not particularly suitable for application to a mobile phone or the like that requires a reduction in size.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a portable information terminal capable of irradiating a subject uniformly during imaging with a simple configuration.

  The present invention includes a light source disposed in the vicinity of the imaging unit, and a plurality of lens portions that respectively emit light that is superimposed on each other and incident on a specific light irradiation region including the imaging region of the imaging unit. And a fly eye lens.

  According to the portable information terminal of the present invention, it is possible to irradiate a subject uniformly during imaging with a simple configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a mobile phone as seen from the front side, FIG. 2 is a perspective view of the mobile phone as seen from the back side, and FIG. 3 is a line II in FIG. FIG. 4 is an exploded perspective view showing the main part of the lid, FIG. 5 is an exploded perspective view showing the main part of the illumination unit, and FIG. 6 is the light irradiation of the imaging region of the camera unit and each lens part. FIG. 7 is an explanatory view showing the relationship between the angle of view of the camera unit and the light irradiation angle of the illumination unit, and FIG. 8 is a cross-sectional view of the principal part showing a modification of the fly-eye lens.

  In FIG. 1, reference numeral 1 denotes a mobile phone with a camera as an example of a portable information terminal. In the present embodiment, the mobile phone 1 is a mobile phone having a structure in which the phone body 5 and the lid 6 can be folded together via a hinge 7.

  In the telephone body 5, a plurality of operation keys 10 are exposed on the inner surface (front side) facing the lid 6 when folded, and a sound collection unit 11 of a microphone (not shown) is opened. .

  In addition, the lid 6 has a sounding portion 15 of a speaker (not shown) opened on the inner surface (front side) facing the main body 5 at the time of folding. The display surface of the main display unit 16 composed of a Liqid Crystal Display) is exposed. Further, on the outer surface side (back surface side) of the lid 5, the display surface of the sub-display unit 17 made of, for example, an LCD is exposed through the optical cover 20, and the operator himself or a surrounding object, a subject such as a landscape is displayed. The lens surface of the camera unit 18 as an imaging unit capable of imaging, and the lens surface of the illumination unit 19 that can appropriately illuminate the subject during imaging using the camera unit 18 are exposed through the optical cover 20.

  As illustrated in FIG. 4, the lid body 6 includes a housing 25 that is divided and formed by, for example, an inner housing portion 26 and an outer housing portion 27 that are resin molded products.

  The inner housing portion 26 has an opening for the sound listening portion 15 of the speaker, and a window portion 30 for exposing the display surface of the main display portion 16 to the outside (see FIG. 1). A pair of locking claws 32 for locking the built-in circuit board 31 protrudes toward the outer surface side.

  The outer housing portion 27 is provided on the inner housing portion 26, and a concave portion 35 for fitting the optical cover 20 is formed on the surface of the outer housing portion 27. Further, the sub display portion 17 is provided on the concave portion 35. The window portions 36, 37, and 38 for exposing the display surface, the lens surface of the camera unit 18, and the lens surface of the illumination unit 19 are opened.

  The circuit board 31 holds the speaker, the main display unit 16 and the like on the inner surface side thereof by electrical connection or the like, and holds the sub display unit 17, the camera unit 18, the illumination unit 19 and the like on the outer surface side. To do. The circuit board 31 is fixed to the inner casing portion 26 by engaging the engaging claw 32 with the edge portion thereof, and at this time, the speaker held on the front side faces the listening portion 15 (not shown). 1), the display surface of the main display portion 16 is exposed to the outside from the window portion 31 (see FIG. 1). On the other hand, the display surface of the sub-display unit 17 fixed to the inner surface side housing via the circuit board 31 and the lens surfaces of the camera unit 18 and the illumination unit 19 include the outer housing portion 27 on the inner housing portion 26. When it is crowned, it is exposed to the outside through the windows 36 to 38.

Next, detailed configurations of the camera unit 18 and the illumination unit 19 will be described.
The camera unit 18 includes, for example, a single-focus imaging lens 40, an imaging element 41 made of a CCD or CMOS transistor, and a camera housing 42 that houses these. As shown in FIG. 3, in this embodiment, the camera housing 42 has a substantially cylindrical lens housing portion 42 a that protrudes to the outer surface side, and the light of the imaging lens 40 that the lens housing portion 42 a holds inside the distal end side. On the axis, the imaging element 41 positioned via the spacer 43 is opposed.

  Here, in this embodiment, the camera unit 18 has its imaging area (effective imaging area) Ac set to a rectangular imaging area by various specifications such as the imaging lens 40 and the imaging element 41 (see FIG. 6). The angle of view α (see FIG. 7) with respect to the optical axis Oc is set to 53 °, for example. The camera unit 18 has a limit distance (approaching imaging limit distance P) at which close-up photography is possible, for example, set to 100 mm.

  The illumination unit 19 includes an LED substrate 50 that holds a light emitting diode (LED) 50 a as a light source, and a lens optical system unit 51 that is provided on the LED substrate 50. As shown in FIGS. 3 to 5, the LED board 50 is fixed to the circuit board 31 adjacent to the camera unit 18, and a plurality of (for example, two each) latches are provided on the edge portions facing each other. A recess 53 is provided.

  As shown in FIGS. 3 and 5, the lens optical system unit 51 includes a lens housing 55, and a collimator lens 56 and a fly-eye lens 57 housed and held in the lens housing 55.

  As shown in FIG. 5, in this embodiment, the lens housing 55 has a substantially rectangular tube shape, the LED insertion port 60 is opened at the lower end, the illumination light exit port 61 is opened at the upper end, A lens insertion opening 62 is opened on one side. The lens housing 55 has a pair of collimator lens grooves 63 and a pair of fly-eye lens grooves 64 facing each other on the inner surfaces of the side walls facing each other. Further, on the lens grooves 63 and 64, Locking holes 63a and 64a are provided. In addition, the lens housing 55 has a locking claw portion 65 that protrudes corresponding to the locking recess 53 of the circuit board 31 at the lower end of each side wall facing each other.

  The collimator lens 56 is a lens for converting the light incident from the LED 50a into parallel light and emitting the parallel light, and has, for example, an emission surface protruding upward on a substantially rectangular lens substrate 56a. In addition, the collimator lens 56 has protrusions 56b that are inserted into the respective collimator lens grooves 63 of the lens housing 55 at both ends of the lens substrate 56a facing each other, and each collimator is provided on each protrusion 56b. A locking portion 56 c that locks in the locking hole 63 a on the lens groove 63 is provided.

  The fly-eye lens 57 is a lens for converting incident light into uniform light having a specific shape and emitting it. The fly-eye lens 57 protrudes upward and downward, for example, onto a lens substrate 57a having a substantially rectangular shape. A plurality of (for example, 4 × 6) lens portions 58 having an emission surface are provided in a matrix. In this embodiment, each lens unit 58 is a planar rectangular lens unit in which, for example, the focal position of parallel light incident from the collimator lens 56 is set on the exit surface (see FIG. 3). As shown in FIG. 6, each light beam l emitted from each lens unit 58 has a rectangular shape corresponding to the planar shape of the lens unit, and most of them overlap each other on a rectangular light irradiation region Al. Irradiate uniformly with Al. The fly-eye lens 57 has ridges 57b that are inserted into the fly-eye lens grooves 64 of the lens housing 55 at both ends of the lens substrate 57a facing each other. Further, on the ridges 57b, Each of the collimator lens grooves 64 has a locking portion 57c that locks in the locking hole 64a.

  These lenses 56 and 57 are accommodated and held in the lens housing 55 via the lens insertion port 62, and at this time, the projections 56b and 57b are inserted into the lens grooves 63 and 64, respectively. , 57 is positioned in the optical axis direction, and the locking portions 56c, 57c are locked in the corresponding locking holes 63a, 64a, so that the lenses 56, 57 are detached from the lens housing 55. Prevention is realized. Here, reference numeral 66 in FIG. 3 denotes a side plate. The side plate 66 is inserted into the lens housing 55 after the lenses 56 and 57 are accommodated in the lens housing 55 by, for example, sticking with an adhesive tape or the like. 62 is closed. In the lens optical system unit 51 in which the collimator lens 56 and the fly-eye lens 57 are housed and held in the lens housing 55 as described above, each latching claw portion 65 is engaged with each locking recess 53 on the LED substrate 50. By stopping, the lighting unit 19 is fixed on the circuit board 31.

  Here, the shape of the light irradiation region Al of the illumination unit 19 is preferably similar to the shape of the imaging region Ac of the camera unit 18. Such a configuration for obtaining the light irradiation region Al is realized by setting the shape of each lens portion 58.

  In this embodiment, the irradiation angle β (that is, an effective irradiation angle for irradiating the light irradiation area Al: see FIG. 7) with the optical axis Ol as the entire illumination unit 19 as a reference is set slightly larger than the angle of view α. Specifically, for example, β = 62 ° is set. Further, the distance between the optical axes Oc-O1 on the circuit board 31 (distance between camera illuminations) is set to 10 mm, for example. With such specifications, the illumination unit 19 has the imaging region Ac as the light irradiation region Al over the proximity imaging limit distance P (= 100 mm) of the camera unit 18, that is, over the entire effective imaging distance of the camera unit 18. It can be included (see FIG. 7).

  According to such a configuration, the illumination unit 19 that irradiates the imaging area Ac of the camera unit 18 is configured to include the fly-eye lens 57, and each lens unit of the fly-eye lens 57 from the LED 50 a via the collimator lens 56. Since the light incident on 58 is overlapped with each other in a specific light irradiation area Al including the imaging area Ac of the camera unit 18, the subject can be obtained with a simple configuration without providing a plurality of light sources on the mobile phone 1. It is possible to uniformly irradiate the imaging region Ac. That is, by superimposing the light emitted from the respective lens portions 58 on the light irradiation area Al, even if the light emitted from the LED 50a is biased, the fly-eye lens 57 can be applied to achieve a good illuminance uniformity. Light can be obtained, and a picked-up image with uniform brightness without spots can be obtained.

  Further, by making the shape of the light irradiation area Al of the illumination unit 19 similar to the shape of the imaging area Ac of the camera unit 18, useless irradiation to the subject can be reduced, and the light emitted from the LED 50a can be reduced. It can be used efficiently.

  Here, as shown in FIG. 8, each lens portion 58 constituting the fly-eye lens 57 may be constituted by a Fresnel lens. With this configuration, the thickness of the fly-eye lens 57 itself in the optical axis direction can be reduced, and the mobile phone 1 can be more effectively downsized.

  Next, FIGS. 9 and 10 relate to the second embodiment of the present invention, FIG. 9 is an exploded perspective view showing the main part of the lid, and FIG. 10 is an exploded perspective view showing the main part of the illumination unit. Note that this embodiment is mainly different from the first embodiment described above in that the lens housing constituting the illumination unit is formed integrally with the outer housing portion 27. Other similar configurations are denoted by the same reference numerals and description thereof is omitted.

  In this embodiment, the outer casing 27 has a pair of ribs 71 on a flat plate at a position closer to the inner tip. These ribs 71 are used to stiffen the outer casing 27 and to configure the lens casing 70 of the lens optical system in the outer casing 27, and are parallel to each other at positions adjacent to the window 36. Standing up. Each rib 71 has a pair of collimator lens grooves 63 and a pair of fly-eye lens grooves 64 facing each other on the surfaces facing each other. Further, on each lens groove 63, 64, a locking hole 63a, 64a.

  Here, in order to improve the assembling workability of the lenses 56 and 57 in the narrow outer casing 27, the lens insertion directions of the lens grooves 63 and 64 and the convex strips 56b and 57b inserted into the lens grooves 63 and 64, respectively. As shown in FIG. 10, it is preferable that the length is as short as possible within a range that does not impair the holding performance of the lenses 56 and 57.

  According to such a form, in addition to the effects obtained in the first form described above, the number of parts of the illumination unit 19 can be reduced by integrally forming the lens casing 70 in the outer casing 27. This is advantageous in that the structure can be further simplified. In addition, since the lens optical system is configured based on the housing part (outer housing part 27) which is a relatively large component, the assembly accuracy of the lenses 56 and 57 can be improved.

  In each of the above embodiments, an example in which the present invention is applied to a camera-equipped mobile phone has been described. However, the present invention is not limited to this, and can be applied to, for example, a portable personal computer. Of course.

  Of course, when collimated light can be emitted directly from the light source, the collimator lens can be omitted from the illumination unit.

The perspective view which looked at the mobile telephone from the front side in connection with the 1st form of this invention. Same as above, perspective view of mobile phone viewed from the back side Same as above, a cross-sectional view of the main part along the line II in FIG. Same as above, exploded perspective view showing the main part of the lid Same as above, exploded perspective view showing the main part of the lighting unit As above, an explanatory diagram showing the relationship between the imaging region of the camera unit and the light irradiation region of each lens unit As above, an explanatory diagram showing the relationship between the angle of view of the camera unit and the light irradiation angle of the illumination unit Same as above, main part sectional view showing a modification of the fly-eye lens The disassembled perspective view which shows the principal part of a cover body in connection with the 2nd form of this invention. Same as above, exploded perspective view showing the main part of the lighting unit

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Mobile telephone (portable information terminal), 18 ... Camera unit (imaging unit), 19 ... Illumination unit, 50a ... Light emitting diode (light source), 51 ... Lens optical system unit, 57 ... Fly eye lens, 58 ... Lens part , Ac ... imaging region, Al ... light irradiation region
Agent Patent Attorney Susumu Ito

Claims (3)

A light source disposed close to the imaging unit;
A fly-eye lens having a plurality of lens portions that respectively superimpose light incident from the light source on a specific light irradiation region including an imaging region of the imaging unit;
A portable information terminal comprising:   2. The portable information terminal according to claim 1, wherein each of the lens portions is composed of a Fresnel lens.   3. The portable information terminal according to claim 1, wherein the imaging area and the light irradiation area of the imaging unit are similar to each other.

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