Patent Publication Number: US-2005140818-A1

Title: Camera module and portable terminal equipped with the camera module

Description:
FIELD OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a camera module and a portable terminal provided with the camera module.  
      2. Description of the Related Art  
      A camera module having the function of autofocusing (AF) and/or zooming used for a portable terminal such as a mobile telephone is required to be constructed small in size.  
      When a camera module having an autofocusing (AF) function or zooming function is reduced in size, zoom lenses also must be downsized. However, the zoom lenses must me moved in the direction of the optical axis of the lenses in order to change the focal distance thereof. Therefore, it is necessary to downsize the lenses, to secure as long traveling distance of lenses as possible in a small space, and to downsize lens holders for retaining lenses, moving mechanism or driving mechanism thereof. A variety of devisal are required to downsize the camera module while keeping easiness of assembling and adjusting.  
      As a camera module like this, there is disclosed a camera for example in JP 7-63970(hereafter referred to as patent literature 1), in which a cylindrical cam located at the side of the optical system of the camera is driven by a motor to move a lens holder for zooming and a lens holder for focusing. In JP 2003-258971 (hereafter referred to as patent literature 2) is disclosed a camera module with zooming function for integrated into a mobile telephone, which is composed such that a lens holder for zooming and a lens holder for focusing are driven by rotating by hand a cylindrical cam partially exposing outside of the mobile telephone at the side face of the portion where optical system is accommodated.  
      In JP 5-84912 (hereafter referred to as patent literature 3) is disclosed a camera, which is composed such that a pinion gear for moving a zoom lens barrel is accommodated in a cut-out part of the cylindrical part for accommodating the lens barrel, as a result the driving mechanism of the zoom lens barrel is accommodated in a small space with the driving mechanism attached to a light shielding plate. In JP 5-333254 (hereafter referred to as patent literature 4) is disclosed a lens moving device used for a video camera, etc. for moving the lens stably, the device being provided with two guide receiving parts protruding from the periphery of a lens frame holding the circumference of the lens. In Japanese Laid-Open Patent Application No. 2-46413 (hereafter referred to as patent literature 5) is recited a lens barrel as an example of prior art, in which the barrel has a cutout opening part through which each lens frame can be rotated for eliminating deviation in optical axis of lenses.  
      Further, there are known a lens moving mechanism for utilizing the space of lens barrel efficiently, in which a supporting part of the guide of lens frames is provided in a housing retaining a subject side lens and lens frames for zooming and focusing are driven by means of two lead screws (hereafter referred to prior art 1); a lens moving mechanism for configuring the lens barrel in small size, in which are provided a lead screw for zooming in the first quadrant around the optical axis, a lead screw for focusing in the second quadrant, and a guide shaft for guiding lens frames (hereafter referred to prior art 2); and a lens moving mechanism in which a subject side lens is retained in a upper housing, lens frames for zooming and focusing are driven by two lead screws respectively, bearings for the two lead screws and two guide shafts of the lens frames are provided in the upper housing, and CCD is attached to a lower housing (hereafter referred to prior art 3).  
      Further, as a camera module, there are known one which is downsized by locating a lead screw for autofocusing and a lead screw for zooming on one side of the case and making it possible to assemble lenses from one side of the lens barrel of the camera module (hereafter referred to prior art 4); one in which switching between telephotographing and macro-photographing in pan-focus lenses is done by means of a cylindrical cam located in the vicinity of lens frames (hereafter referred to prior art 5); and one in which holders of optical pickup lenses used for video disc player, digital audio player, optical disc file, etc. are made of resin containing fluorine for reducing inertia force by lightening the weight of the holders as far as possible (hereafter referred to prior art 6). In an autofocusing type video camera, shafts of aluminum, etc. coated with fluororesin are used for improving sliding property and abrasion-resistant property (hereafter referred to prior art 7).  
      However, the device disclosed in patent literature 1 is related to a camera module for a video camera, gives no consideration to downsize it to be installed in a portable terminal, and a drive motor is located remote from the optical system in an ample space inside the camera module; the device disclosed in patent literature 2 is related to a small sized camera module to be integrated in a portable terminal, etc., but it is manual operation type and can not be applied to a camera module in which zooming and autofocusing are performed by means of a motor.  
      Patent literature 3 is related to a light shielding mechanism to make it possible to accommodate a zoom lens moving mechanism in a small space and does not teach a composition to secure enough travel distance of the zoom lens in a small space. Patent literature 4 relates to a lens moving mechanism for moving a lens used for a video camera, etc. stably, patent literature 5 relates to an aligning method of lenses, and each of these does not teach a composition to secure enough travel distance of the zoom lens in a small space.  
      According to prior art 1, the space of lens barrel is utilized efficiently, however, it is featured only in that the subject side lens is retained in the housing thereof and the supporting part of the lens frames is provided in the housing, a driving device such as a motor is not integrated, and it is difficult to find it informative for composing a camera module.  
      According to prior art 2, although the space around the optical axis is utilized efficiently by locating a lead screw for zooming, a lead screw for focusing, and a guide shaft for guiding lens frames around the optical axis, it is also difficult to find it informative for composing a camera module so that enough travel distance of zoom lens can be secured in a small space. According to prior art 4, although a lead screw for autofocusing and a lead screw for zooming are located at one side of the casing to downsize the camera module, it is difficult to reduce the size enough, for the lead screws are provided separately for autofocusing and zooming; and according to prior art 3, a driving mechanism and CCD are attached to separate housings and assembly process becomes complicated, so that they can not serve as a useful reference for composing a small sized camera module.  
      According to prior art 5, switching between telephotographing and macro-photographing is done by means of a cylindrical cam located in the vicinity of lens frames, this module is for pan-focusing and can not serve as a useful reference when autofocusing mechanism is to be installed.  
      Prior art 6 relates to a pickup lens holder for optical disc, is informative for reducing weight but can not serve as a useful reference from the point of view of downsizing a camera module.  
      In prior art 7, shafts made of aluminum must be coated with fluororesin, which results in an increased cost.  
     SUMMARY OF THE INVENTION  
      The object of the present invention is to provide a camera module constructed such that a sufficient distance of lens movement is secured in a small space even if the function of autofocusing (AF) and/or zooming is incorporated, and a portable terminal equipped with the camera module.  
      To achieve the object mentioned above, the present invention proposes a camera module comprising accommodated in the casing thereof an optical lens system, a lens moving mechanism for moving a plurality of lenses of an optical lens system in a predetermined direction to perform focal adjustment and/or change of image magnification, and a housing composing a casing of the camera module, 
          a lens retaining part formed in said housing for retaining one of the lenses of the optical lens system,     lens holders for accommodating said moving lenses,     protruded portions provided in said lens retaining part for contacting said one of the lenses at least at three points to determine the position of said one of the lenses, and concaved portions provided in said protruded portions such that the peripheral part of said one of the lenses is exposed,     whereby at least one of said lens holders can advance to said concaved portions provided in said protruded portions.        

      Said at least one of lens holders has depressions (second concaved portions) to correspond to said protruded portions in said lens retaining part, and said lens moving mechanism includes a cylindrical cam located in the vicinity of the periphery of said lens holders, a cam bearing part for supporting said cylindrical cam, guide shafts for guiding said lens holders, and guide shaft attaching parts for attaching said guide shafts, and wherein said guide shaft attaching parts and said cam bearing part are formed in one piece with said housing.  
      Further, to achieve the object mentioned above, the present invention proposes a camera module comprising accommodated in a housing composing the casing thereof an optical lens system, a lens moving mechanism for moving a plurality of lenses of the optical lens system in a predetermined direction to perform focal adjustment and/or change of image magnification, wherein are provided lens holder or holders for retaining at least some of the lenses of the optical lens system, a cylindrical cam for moving the lens holder or holders in the direction of the optical axis, and guide shafts for guiding the lens holder or holders in the direction of the optical axis, and therein each of said lens holders has supporting arms extending radially outwardly to be fitted slidably to said guide shafts and a cam follower arm extending radially outwardly in different directions, the arms being formed in one piece with the lens holder, and wherein said cam follower arm extends radially outwardly such that the cam follower arm overlaps in the direction of the optical axis at least partially with at least one of the supporting arms extending in a radial outward direction.  
      It is preferable that said supporting arms and cam follower arm are formed in one piece with said lens holder.  
      Further, said lens moving mechanism includes at least a gear group fitted rotatably to shafts to transmit the driving force of the driving source to said cylindrical cam, and wherein at least a shaft to which the last gear among said gear group is fitted rotatably (last stage gear shaft) is made of resin and other shafts are made of metal and said last stage gear shaft is formed in one piece with said housing.  
      The camera module of the invention comprises an optical lens system, a housing for composing the casing of the camera module for retaining and positioning at least a part of the optical lenses of the optical lens system and at least a lens holder and a accommodating a lens moving mechanism, a cylindrical cam located in the vicinity of the periphery of the lens holder or holders and supported for rotation for moving the lens holder or holders in the direction of the optical axis, a driving source, a last gear for driving the cylindrical cam, a gear or gears located between the last gear and the driving source, a shaft made of resin for fitting the last gear for rotation, shaft or shafts for fitting the gear or gears for rotation, and a supporting portion for supporting the shaft or shafts.  
      Further, the camera module of the invention comprises a housing composing the casing of the camera module, an optical lens system, a lens retaining part for retaining at least a part of the lenses of the optical lens system, a lens holder or holders for retaining moving lenses, a cylindrical cam located in the vicinity of the periphery of the lens holder or holders and supported for rotation for moving the lens holder or holders in the direction of the optical axis, cam bearing parts for supporting the cylindrical cam, gears for transmitting driving force of the driving source to the cylindrical cam, shafts for fitting the gears for rotation, a supporting part supporting the shafts, a lens retaining part for retaining and positioning at least an object side lens positioned nearest to the object of shooting; and the cam bearing parts, the shaft supporting part, and the lens retaining part are formed in one piece with the housing and the housing is made of resin. The cam bearing part is located in the vicinity of the lens retaining part and the shaft supporting part is located between the cam bearing part and the driving source.  
      Further, the camera module of the invention comprises an optical lens system, a housing composing the casing of the camera module and accommodating a moving mechanism and an image pickup device, a lens retaining part formed in one piece with the housing for retaining a part of lenses of the optical lens system, a mounting part provided in the housing for mounting the image pickup device, a lens holder or holders for retaining moving lenses of the optical lens system, guide shafts for guiding the lens holder or holders, supporting arms provided to each of the lens holders to be fitted to the guide shafts for sliding, a cam follower arm provided to each of the lens holders, a cylindrical cam to which the cam follower arm contacts for the lens holder to be moved; and the supporting arms and the cam follower arm are formed to extend radially in relation to the center of the lens holder, i.e. the optical axis with a certain angle such that at least one of the supporting arms overlaps at least partially with the cam follower arm. It is preferable that the supporting arms and the cam follower arm are formed in one piece with the lens holder. The bearing part for supporting the cylindrical cam and the supporting part of the guide shafts are formed in one piece with the housing. Further, the bearing part for supporting the cylindrical cam and the supporting part of the guide shafts are located near marginal parts inside the housing and gears for transmitting the driving force of the driving source are arranged between the driving source for driving the cylindrical cam and the cylindrical cam.  
      Further, in the camera module of the present invention, a positioning part is provided in said housing for locating said driving source to be fixed there, the positioning part having an opening part, and said gear group is arranged in the space near toward the part where said one of the lenses is located between said cylindrical cam and said driving source.  
      In the preferred embodiment of the invention, said housing is made of resin containing fluorine, and said cylindrical cam is made of resin.  
      To achieve the object mentioned above, the present invention proposes a portable terminal-having a camera module which comprises: a housing accommodating an optical lens system, a lens moving mechanism for moving at least some of the lenses of the lens system, and an image pickup device and composing the casing of a camera module, a lens retaining part formed integrally in the housing for retaining one of the lenses of the lens system, a attaching part provided in said housing for attaching said image pickup device, lens holders for retaining the lenses composing said optical lens system, protruded portions provided in said lens retaining part for contacting said one of the lenses at least at three points to determine the position of said one of the lenses, concaved portions provided in said protruded portions such that the peripheral part of said one of the lenses is exposed, guide shafts for guiding said lens holders, supporting arms provided to each of said lens holders for fitting rotatably to said guide shafts, a cam follower arm provided to each of said lens holders, a cylindrical cam contacting to said cam follower arms to allow the lens holders to be moved, whereby one of said lens holders can advance to said concaved portions provided in said protruded portions, wherein at least one of said supporting arms and said cam follower arm extending radially in different directions different by a certain angles from each other, and wherein said cam follower arm overlaps with at least one of the supporting arms in the direction of the optical axis; a case body equipped with the camera module; and an operating portion provided to said case body to operate said camera module mounted to said case body. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of an embodiment of the camera module according to the present invention.  
       FIG. 2  is a perspective view of the first housing of the casing of the embodiment of the camera module according to the present invention.  
       FIG. 3  is a plan view of the first housing of  FIG. 2 .  
       FIG. 4  is a perspective view showing the state when guide shafts and gear shafts are being attached to the first housing of  FIG. 2 .  
       FIG. 5  is a perspective view showing the state when gears are being fitted rotatably to the gear shafts shown in  FIG. 4 .  
       FIG. 6  is a perspective view showing the state when gears have been fitted rotatably to the gear shafts shown in  FIG. 4 .  
       FIG. 7  is a perspective view of moving the lens assemblies and cylindrical cam of the camera module according to the present invention.  
       FIG. 8  is a perspective view showing when the moving lens assemblies and cylindrical cam of  FIG. 7  are attached to the first housing.  
       FIG. 9A  is a top view of one of lens holders, and  FIG. 9B  is a bottom view of the lens holder.  
       FIG. 10 a  perspective view showing the state when the lens holder of  FIG. 9A  is mounted to the first housing.  
       FIG. 11  is a perspective view of the second housing together with the drive motor to be fixed to the second housing and the flexible band attached with an optical sensor and attached to the drive motor.  
       FIG. 12  is a perspective view of the second housing showing the state when the drive motor is fixed thereto facing to the cut-out opening part thereof.  
       FIG. 13  is a perspective view of the second housing showing the state when the drive motor is fixed thereto facing to the cut-out opening part thereof together with the flexible band attached to the drive motor.  
       FIG. 14  is a perspective view of the camera module before the CCD is attached for explaining attaching thereof.  
       FIG. 15  is a schematic view of the portable terminal installed with the camera module according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      A preferred embodiment of the present invention will now be detailed with reference to the accompanying drawings. It is intended, however, that unless particularly specified, dimensions, materials, relative positions and so forth of the constituent parts in the embodiments shall be interpreted as illustrative only not as limitative of the scope of the present invention.  
       FIG. 1  is a perspective view of an embodiment of the camera module according to the present invention,  FIG. 2  is a perspective view of the first housing of the casing of the embodiment of the camera module according to the present invention,  FIG. 3  is a plan view of the first housing of  FIG. 2 ,  FIG. 4  is a perspective view showing the state when guide shafts and gear shafts are being attached to the first housing of  FIG. 2 ,  FIG. 5  is a perspective view showing the state when gears are being fitted rotatably to the gear shafts shown in  FIG. 4 ,  FIG. 6  is a perspective view showing the state when gears have been fitted rotatably to the gear shafts shown in  FIG. 4 ,  FIG. 7  is a perspective view of moving the lens assemblies and cylindrical cam of the camera module according to the present invention,  FIG. 8  is a perspective view showing when the moving lens assemblies and cylindrical cam of  FIG. 7  are attached to the first housing,  FIG. 9A  is a top view of one of lens holders and  FIG. 9B  is a bottom view of the lens holder,  FIG. 10 a  perspective view showing the state when the lens holder of  FIG. 9A  is mounted to the first housing,  FIG. 11  is a perspective view of the second housing together with the drive motor to be fixed to the second housing and the flexible band attached with a optical sensor and attached to the drive motor,  FIG. 12  is a perspective view of the second housing showing the state when the drive motor is fixed thereto facing to the cut-out opening part thereof,  FIG. 13  is a perspective view of the second housing showing the state when the drive motor is fixed thereto facing to the cut-out opening part thereof together with the flexible band attached to the drive motor,  FIG. 14  is a perspective view of the camera module before the CCD is attached for explaining attaching thereof, and  FIG. 15  is a schematic view of the portable terminal installed with the camera module according to the present invention.  
      In the drawings, the same component is indicated by the same reference number. Referring to  FIG. 1 , reference numeral  11  is a camera casing (hereafter referred to simply as casing) made of, for example, polycarbonate containing fluorine, the casing  11  consisting of a first housing  21  (see  FIG. 2 ) and a second housing  41  (see  FIG. 11, 12 ). Reference numeral  12  is an optical lens system,  13  is a lens moving mechanism,  11   a  is an opening part of the casing  11 , a hatched part indicated by reference numeral  14  is a cover plate (light shielding plate) covering the opening part  11   a . Reference numeral  15  is a CCD which is attached to the casing  11  at the lower side thereof in the drawing and by the light received through the optical lens system  12  is converted to an electric signal. Reference numeral  16  is an optical sensor (light emitting device and photoreceptor device) attached to the side of the casing  11 . The optical sensor  16  detects the rotation position or rotation angle or rotated angles of the cylindrical cam and the distance of the position of the moving lens group or groups from a reference position is calculated. The optical sensor  16  is attached to a flexible band  40  (see  FIG. 11 ) which also serves as a covering plate to cover an opening  41   f  provided on a side wall  41   c  of the second housing  41 .  
      Referring to  FIG. 2 ,  FIG. 3 , and  FIG. 10 , reference numeral  21  is the first housing of the casing  11 . A first thick side wall part  21   a  and a second thick side wall part  21   b  extend from the upper part (base part) of the first housing  21 . Cutout opening parts  11   a  and  11   b  are defined between the thick side wall parts  21   a  and  21   b . Reference numeral  22  is an opening formed in the base part (upper part in  FIG. 2  of the first housing) for retaining the object side fixed lens of the optical lens system (not shown in  FIG. 2 ) of the camera module,  22   a  is an annular formation extending radially inwardly from the inside surface of the opening  22 , and  22   b &#39;s are reference surfaces on a plurality of protruded portions protruding radially inwardly of the annular formation  22   a , in the embodiment three protrusions being formed. Reference numerals  22   c &#39;s are salient parts for positioning the object side fixed lens so that its center coincides with the center line of the optical lens system,  22   d &#39;s are concaved portions of the annular formation  22   a  to allow a lens holder  34  (see  FIG. 7 ) to advance into the space surrounded with the annular formation  22   a , and  23 &#39;s are reference surfaces, which serve as reference surfaces when assembling, on a plurality of protrusions provided on the outer face of the base part of the first housing  21 , in the embodiment three protrusions being formed.  
      In  FIG. 4  is shown the first housing of  FIG. 2  in an upside-down position. In the drawing, reference numeral  24  is a mounting portion provided near the opening  22  to mount a lens moving mechanism (not shown in  FIG. 4 ) to be mounted to the base part of the first housing  21 . On the mounting portion  24  are formed a cam mounting part  27  for mounting a cylindrical cam mentioned later and a shaft body  28  protruding upward near the cam mounting part  27 . Reference numerals  25   a  and  25   b  are a first and a second hole for fixing a first and a second shaft (guide shafts) respectively, the holes  25   a  and  25   b  being provided on the base part near the peripheral part of the opening  22  with angular spacing of about 180° to each other. Reference numerals  25   c  and  25   d  are a third and a fourth hole for fixing a third shaft and a fourth shaft respectively. Reference numerals  26   a ,  26   b ,  26   c , and  26   d  are a first, a second, a third, and a fourth shaft made of, for example, stainless steel. Among them, the first and second shaft  26   a  and  26   b  are guide shafts for guiding moving lens groups (not shown in  FIG. 4 ) of the optical lens system and inserted into the first and second hole  25   a  and  25   b  respectively to be fixed there. The third and fourth shaft are inserted into the third and fourth hole  25   a  and  25   b  respectively to be fixed there. Reference numeral  46  is a bolt hole for a screw bolt (not shown in the drawing) to fasten the first housing  21  and the second housing  41  (see  FIGS. 11, 12 ).  
      Referring to  FIG. 5 , reference numerals  29   a - 29   d  are gears to be fitted rotatably to the third and fourth shaft  26   c  and  26   d  and to the shaft part  28  as indicated by arrows with broken lines. A first gear  29   a  is fitted rotatably to the third shaft  26   c  and then a second gear  29   b  is fitted rotatably to the same on the first gear  29   a . A third gear  29   c  is fitted rotatably to the fourth shaft  26   d  and a fourth gear  29   d  is fitted rotatably to the shaft part  26 . The second gear  29   b  meshes with the third gear  29   c , the third gear  29   c  meshes with the first gear  29   a , and the first gear  29   a  meshes with the fourth gear  29   d  (see  FIG. 6 ). As mentioned later, the gear of a driving motor is allowed to mesh with the second gear  29   b  and the rotation driving force of the driving motor is transmitted to the cylindrical cam via the gears  29   b ,  29   c ,  29   a , and  29   d  (See  FIG. 8 . In  FIG. 6  and  FIG. 8 . The gear  29   b  is shown on the way of being fitted rotatably to the shaft  26   c , the gear  29   b  will be pushed down until it meshes with the gear  29   c .). Reference numeral  45  is a side end face of the side wall part  21   a  of the first housing  21 , where a side end face  44  of the second housing  41  mentioned later is jointed,  47  is an adhesive-joining part for joining the first housing  21  with the second housing  41  with an adhesive agent, the joining part  45  being located at a corner opposing about diagonally to the bolt hole  46  of the first housing  21 ,  58  is a concave formed when the first housing  21  and second housing  41  are assemble and fixed to each other as shown in  FIG. 14 , the concave  58  serving as a well for retaining an adhesive agent for adhering a board mounted with the CCD  15 .  
       FIG. 7 ,  FIG. 8 , and  FIG. 9  show moving-lens assemblies and a cylindrical cam, the state they are assembled to the first housing, and a top and bottom view of a moving-lens holder respectively in a state the camera casing in  FIG. 1, 2  is turned upside-down. In the drawings, reference numeral  30  is a cylindrical cam for driving a lens driving mechanism  13  assembled to the first housing  21 . The cylindrical cam  30  has a cylindrical part  30   a , a spiral formation  30   b  around the periphery, and a journal  30   e  at the lower end. On the spiral formation  30   b  are defined an upper spiral cam face  30   c  and a lower spiral cam face  30   d . The upper spiral face  30   c  is a cam face for zoom focusing, and the lower spiral face  30   d  is a cam face for zooming. The journal  30   e  is inserted into a bearing bore provided in the cam mounting part  27  of the first housing  21 . The cylindrical cam  30  is provided with a bearing hole in the upper end part thereof to receive a shaft part formed in the second housing  41  as explained later to support the upper side of the cylindrical cam  30  for rotation. On the cylindrical part  30   a  of the cylindrical cam  30  is defined a reference line extending in the vertical direction in  FIG. 2 , although not shown in  FIG. 7 , the reference line being different, for example, in color from the color of the peripheral surface of the cylindrical part  30   a.    
      Reference numeral  31  and  32  are a first lens assembly and a second lens assembly respectively having moving lenses attached thereto,  33  and  34  are lens holders of the first and second lens assembly respectively. Reference numeral  33   a  and  33   b &#39;s are supporting arms of the lens holder  33 , the arms  33   a  and  33   b &#39;s extending from the periphery of the lens holder  33  radially outwardly, and  33   c  is a cam follower arm to be brought into contact with the upper spiral cam face  30   c , the cam follower arm  33   c  also extending from the periphery of the lens holder  33  radially outwardly. Reference numeral  34   a  and  34   b &#39;s are supporting arms of the lens holder  34 , the arms  34   a  and  34   b &#39;s extending from the periphery of the lens holder  34  radially outwardly, and  34   c  is a cam follower arm to be brought into contact with the lower spiral cam face  30   d , the cam follower arm  34   c  also extending from the periphery of the lens holder  34  radially outwardly. Reference numeral  34   d &#39;s are depressions (second concave portions) formed on the periphery of the lower part of the lens holder  34 , which can be recognized clearly in  FIG. 9A . By virtue of the depressions  34 &#39;s, the lens holder  34  can be advanced near to the object side fixed lens without interfered by the protruded portions of the annular formation  22   a  in  FIG. 2 . Reference numeral  35  and  36  are moving lens groups retained by the lens holders  33  and  34  respectively, and  37  is a spring member connected to the lens holders  33  and  34  so that the holders pull one another.  
      The lens holder  33  has a supporting arm  33   a  and a pair of supporting arms  33   b &#39;s, each being extending radially outwardly from the periphery thereof in directions substantially opposite to each other. Each of the supporting arms  33   b &#39;s is provided to be located apart to each other by a certain distance in the direction of the optical axis. The lens holder  34  has a supporting arm  34   a  and a pair of supporting arms  34   b &#39;s, each being extending radially outwardly from the periphery thereof in directions substantially opposite to each other. Each of the supporting arms  34   b &#39;s is provided to be located apart to each other by a certain distance in the direction of the optical axis. Each of the lens holders  33  and  34  is provided with a cam follower arm  33   c  and  34   c  extending radially outwardly deviated by an angle θ (see  FIG. 9B ) from the direction of the pair of supporting arms  33   b &#39;s and  34   b &#39;s and adjacent to the pair of supporting arms  33   b &#39;s and  34   b &#39;s respectively, the cam follower arm  33   c  overlapping with the supporting arms  33   b &#39;s and the cam follower  34   c  overlapping with one of the supporting arm  34   b &#39;s at least partially in the direction of the optical axis.  
      A guide groove is provided in each of the supporting arms  33   a  and  34   a  of the lens holders  33  and  34  for fitting slidably to the first shaft (guide shaft)  26   a  in  FIG. 4 , and a guide hole is provided in each of the supporting arms  33   b &#39;s and  34   b &#39;s for fitting slidably to the second shaft (guide shaft)  26   b  in  FIG. 4 . The supporting arms  33   b &#39;s and  34   b &#39;s of the lens holders  33  and  34  are formed such that the holders are fitted slidably to the second shaft  26   b  in a state that one of the supporting arms  33   b &#39;s and one of the supporting arms  34   b &#39;s cross each other in the direction of the optical axis, that is, the lower supporting arm of the lens holder  33  is positioned between the upper and lower supporting arms of the lens holder  34 . With this composition, the supporting arms  33   b &#39;s can be formed to be apart by an increased distance to each other and also the supporting arms  34   b &#39;s can be formed to be apart by an increased distance to each other. Therefore, when forces for moving the lens holders  33  and  34  in the direction of the optical axis are exerted slantwise in relation to the optical axis on the lens holders  33  and  34  from the spiral cam faces  30   c  and  30   d  via the cam follower arms  33   c  and  34   c , the lens holders  33  and  34  can be moved smoothly along the guide shaft  26   b , for the tilting of the lens holders caused by the gap between the guide shaft  26   b  and the guide holes of the supporting arms  33   b &#39;s and  34   b &#39;s becomes small by virtue of the increased distance between each of the supporting arms  33   b &#39;s and between each of the supporting arms  34   b &#39;s. Referring to  FIG. 11 ,  FIG. 12 , and  FIG. 13 , reference numeral  38  is a driving motor (stepping motor, for example) composing the lens moving mechanism  13 , and  38   a  is a gear attached to the motor shaft of the driving motor  38 . The driving motor  38  is located above the third gear  29   c  with the gear  38   a  side down in  FIG. 11  so that the gear  38   a  meshes with the second gear  28   b  shown in  FIG. 8 . Reference numeral  39  is a boss provided on a peripheral part of the driving motor  38  for attaching one of branched parts of the flexible band  40 . The optical sensor  16  is attached to the other of branched parts of the flexible band  40  to face to the cylindrical cam  30 . The flexible band  40  is bent in the direction perpendicular to the optical axis to be extended outward of the second housing  41  to which the driving motor  38  is attached.  
      Reference numeral  41   a  is a supporting face for supporting an end of the driving motor  38  to define the vertical position thereof, and  41   b  is an opening at the supporting face  41   a  for inserting the gear  38   a  of the driving motor  38  which meshes with the third gear  29   c . Reference numeral  41   c  is a side wall of the second housing  41 . An overhanging section is formed at an upper corner of the side wall  41   c , and a shaft part is formed to protrude downward from the overhanging section, reference numeral  41   d  indicating a lightening hole of the shaft part. The upper side of the cylindrical cam  30  is supported rotatably by this shaft part by fitting the bearing hole provided in the upper part thereof as mentioned before. Reference numeral  41   f  is an opening for allowing the optical sensor for detecting the reference line on the cylindrical cam to face the cylindrical cam  30 , and  42  is a cutout opening part extending vertically on a side wall of the second housing  41  with the upper side thereof open (see  FIG. 12, 13 , and  14 ). The side wall of the second housing  41  is thin near the cutout opening part  42 , and the width of the cutout opening part  42  is smaller than the diameter of the driving motor  38 . Further, the second housing  41  has cutout parts on its side in addition to the opening  41   f  and cutout opening part  42  to define cutout opening parts  11   a  and  11   b  when the second housing  41  is assembled to the first housing  21  as shown in  FIG. 2 . The depth of the second housing  41  in a plane perpendicular to the center axis of the lens holders  33  and  34  (optical axis) is about the same as the sum of the diameter of the cylindrical cam  30  and the diameter of the driving motor  38 . A hatched part  43  in  FIG. 13  is a cover plate to cover the portion the flexible band  40  is drawn out of the second housing  41 . Reference numeral  44  is a side end face of the second housing  41  to be joined to the side end face  45  of the side wall part  21   a  of the first housing  21 , and  59  is a boss for providing a screw hole corresponding to the bolt hole  46  of the first housing  21  to fix the first housing  21  to the second housing  41  by means of a screw bolt.  
       FIG. 14  shows a perspective view of the state the second housing is attached to the first housing and moving lens assemblies and driving motor  38  are assembled to the housings. In the drawing, a hatched part indicated by reference numeral  42   a  is a cover plate covering the cutout opening part  42  for light shielding, a hatched part indicated by reference numeral  42   e  is a cover plate covering the cutout opening part  11   b  for light shielding. Reference numeral  48 &#39;s are reference points for measurement when the CCD  15  shown in  FIG. 1  is fixed, and  60   a  and  60   b  are image pickup device attaching parts for bonding a board mounted with the CCD  15 . Referring to  FIG. 15 , reference numeral  50  is a portable telephone as an example of portable terminal,  51  is an operating portion,  52  is a display made of liquid crystal for example,  53  is a first case part equipped with the operation portion  51 ,  54  is a second case part equipped with the display  52 ,  55  is a hinge mechanism, and  56  is a camera module.  
      The camera module according to the embodiment is constructed such that; the camera casing  11  is composed of the first housing  21  made of resin such as, for example, polycarbonate containing fluorine, which has increased durability and good sliding property, and the second housing  41 ; the opening  22  for retaining the object side fixed lens is provided in the base part of the first housing  21  as shown in  FIG. 2 ,  FIG. 3 , and  FIG. 10 ; the annular formation  22   a  is formed to extend radially inwardly from the inside surface of the opening  22 ; and reference surfaces  22   b &#39;s for defining the position of the object side fixed lens in the direction of the optical axis are established on the upper faces of a plurality of protruded portions of the annular formation  22   a  protruding radially inwardly. On the other hand, depressions  34   d &#39;s are formed on the periphery of the lower part of the lens holder  34  retaining the moving lens group  36  so that the lens holder  34  can be advanced into the space surrounded by the annular formation  22   a  without interfered by the protruded portions, on which the reference surfaces  22   b  are defined, of the annular formation  22   a.    
      With the configuration, the lens holder  34  which moves with moving lens group  36  retained in it can advance into the space surrounded with the annular formation  22   a  at the opening  22 , and enough moving distance of the lens holder  34  for zooming can be secured in a small space, thus a small camera module with sufficient zoom ratio can be provided.  
      As shown in  FIG. 4 , the mounting portion  24  for mounting the lens moving mechanism is formed in the base part of the first housing  21  adjacent to the opening  22 , the first and second shaft mounting holes  25   a  and  25   b  are provided near the peripheral part of the opening  22  at an angle spacing of about 180° and the third and fourth shaft mounting holes  25   c  and  25   d  are provided in the mounting portion  24 .  
      The first to fourth shafts  26   a - 26   d  made of stainless steel for example are inserted into the first to fourth holes  25   a - 25   d  of the base part of the first housing  21  from upper side as indicated by arrows with broken lines. The cam mounting part (cam bearing part)  27  for mounting the cylindrical cam  30  is formed in the vicinity of the mounting portion  24  of the base part, and a shaft body  28  is formed integrally with the first housing  21  to protrude upward in the mounting portion  24 . The first and second shafts  26   a  and  26   b  are used as guide shafts for guiding moving lens groups. To the third shaft  26   c  are fitted rotatably the first gear  29   a  and the second gear  29   b  as indicated by one of the arrows with broken lines in  FIG. 5 .  
      To the fourth shaft  26   d  is fitted rotatably the third gear  29   c , which meshes with the first gear  29   a . Further the fourth gear  29   d  is fitted rotatably to the shaft body  28  to mesh with the first gear  29   a . Thus, the first to fourth gears  29   a - 29   d  are put together (see  FIG. 6 ). The fourth gear  29   d  is the last stage gear to mesh with the gear of the cylindrical cam  30  to transmit rotation force to the cylindrical cam. In the embodiment, the shaft body  28  to which the last stage gear  29   d  is fitted rotatably is integral with the first housing and accordingly made of the same resin material of the housing.  
      By making the shafts  26   c  and  26   d , to which the gears  29   a - 29   c  for transmitting driving force to drive the last gear  29   d  which meshes with the gear of the cylindrical cam, of metal, gears  29   a - 29   c  can be reduced in size, which contributes to downsizing the camera module and reducing mechanical noise, because the shafts  26   c ,  26   d  made of metal can be reduced in their diameters, for the rotation speeds of the gears are high but the loads exerting on the gears are light.  
      As the shaft body  28  to which the last stage gear  29   d  is fitted rotatably is formed integrally with the first housing and therefore is made of resin, it is light even if its diameter is increased for securing enough strength. Further, by forming the shaft body integrally with the first housing, the number of parts and assembling man-hours can be reduced.  
      The bearing part to support the cylindrical cam for defining the movement of the lens holders  33  and  34  is formed in the first housing so that a particular bearing needs not be provided, and the first housing is made of resin containing fluorine so that the bearing part has durability and good sliding property as a bearing. Therefore, as no particular bearing is needed, the number of parts is reduced, downsizing and weight saving of the camera module are possible, and the strength of the housing is increased by adding fluorine to the resin material of the housing.  
      In the embodiment of the camera module of  FIG. 1 , the casing  11  is made of, for example, resin such as polycarbonate containing fluorine to increase durability and improve sliding property, the casing being composed of the first housing  21  shown in  FIG. 2  to which the driving mechanism  13  is mounted and the second housing  41  to which the motor  38  shown in  FIG. 12  is attached; and the board mounted with the CCD  15  for picking up images, optical sensor  16  consisting of a light emitting device and a photoreceptor device, and cover plates (light shielding member) such as indicated by reference numerals  14 ,  41   e  are attached to the casing to compose the camera module to be small in size to be used as an image pickup device for the portable telephone  50  shown in  FIG. 15  as an example of portable terminals. Shooting and zooming operation of the camera module can be done by manipulating the operating portion  51  shown in  FIG. 15 .  
       FIG. 15  is a plan view of the portable telephone  50  shown in a state the operating portion  51  and display  52  are viewable (opened state); the first case  53  equipped with the operating portion  51  and the second case  54  mounted with the display  52  are connected with the hinge mechanism  55 , and the first and second case  53 ,  54  can turn around the hinge mechanism  55 .  
      The camera module is mounted to the second case  54  so that the optical lens system  12  is located at the position indicated by a double circle of broken line in the drawing, photographing is done by the camera module by manipulating a designated button on the operating portion  51 , and the photographed image is displayed on the display  52 . Therefore, the camera module is required to be composed very small in size. Zooming operation of the camera module can be possible by manipulating another designated button of the operating portion  51 .  
      The embodiment of the camera module has the first housing  21  shown in  FIG. 1 ,  FIG. 2 , the opening  22  for accommodating the object side fixed lens of the optical lens system  12  being defined in the base part (upper part in  FIG. 2 ) of the first housing  21 , the annular formation  22   a  being formed to extend radially inwardly around the inner surface of the opening  22 , the annular formation  22   a  having a plurality of protrusions protruding radially inwardly-with a reference surface  22   a  defined on the upper surface of each of the protrusions, between the protrusions being formed concaved portions  22   d  for allowing the lens holder  34  to advance to the annular formation  22   a . Salient parts  22   c &#39;s for defining the center position of the object side fixed lens of the optical lens system  12  are provided on the inner surface of the opening  22  to extend from the reference surfaces  22   b &#39;s. The position in the direction of the optical axis of the fixed lens is determine by the reference surfaces  22   b &#39;s and central position thereof is determined by the salient parts  22   c &#39;s accurately.  
      The first housing  21  has the base part having the reference surfaces  22   b &#39;s for mounting the object side fixed lens of the optical lens system  12  thereon and reference surfaces  23 &#39;s which serve as reference surfaces when the lens assemblies, lens moving mechanism are assembled automatically onto the base part, the lens assemblies  31 ,  32  comprising the lens holders  33 ,  34  and the lens moving mechanism comprising the cylindrical cam  30  and gears  29   a - 29   d  being able to be assembled onto the base part from the open side opposite to the base part of the first housing. Therefore, moving lens groups and lens moving mechanism can be incorporated and adjusted with ease and automatic assembling with good accuracy can be made possible. Further, the first housing  21  can be removed from the mold in a direction with the accuracy of the reference surfaces side secured when casting.  
      The first housing  21  has the first side wall part  21   a  and second side wall part  21   b  continuing to the base part, the portions other than the side walls being cutout opening parts, and on the upper face of the base part are formed a plurality of protrusions on which the reference surfaces  23 &#39;s are provided (three reference surfaces in the case of example in  FIG. 2 ). These reference surfaces  23 &#39;s are brought into contact with the reference surface of an assembly jig (not shown in the drawings) when the camera module is automatically assembled with the base part side of the first housing  21  down to serve as reference surfaces for securing accuracy in assembling and adjusting the lens assembly and lens moving mechanism.  
      The cylindrical cam  30  is a cam member of nearly cylindrical shape made of metal, resin, or resin containing fluorine and has the cylindrical part  30   a  and spiral formation  30   b  defined on the periphery of the cylindrical part  30   a . On the spiral formation  30   b  are defined the zoom focusing face  30   c  on the upper side thereof in  FIG. 7  and zooming face  30   d  on the lower side thereof in  FIG. 7 . In the case the cylindrical cam  30  is made of resin, it can be made to have lightweight, strength, and durability, and further in the case it is made of resin containing fluorine, the sliding property of the journal  30   e  can be improved. The optical lens system of the camera module of the embodiment is an example of a dual focus type, the zooming face  30   d  is defined such that the second lens assembly  32  for shifting focus point is moved by a predetermined distance by the rotation of the cylindrical cam and after that the lens assembly  32  is not moved by further rotation of the cylindrical cam  30 . The zoom focusing face  30   c  is defined such that the first lens assembly  31  is moved for focusing by the rotation of the cylindrical cam  30  even after the second lens assembly  32  is stopped after it is moved by the predetermined distance.  
      When the cylindrical cam  30  and the first and second lens assemblies are assembled to the first housing  21 , the lower end face of the cam follower arm  33   c  contacts the focusing face  30   c  and the upper end face of the cam follower arm  34   c  contacts the zooming face  30   d . The lens holders  33 ,  34  are connected by means of the spring  37  to be pulling each other. A reference line, although not shown in the drawings, extending in the axial direction of the cylindrical  30  is provided on the cylindrical part  30   a  thereof, the reference line being different, for example, in color from that of the cylindrical part  30   a  so that the line is detected by the optical sensor  16  shown in  FIG. 16  detects the original position of the cylindrical cam  30 .  
      As shown in  FIG. 8 , when the lens-assemblies  31 ,  32  and cylindrical cam  30  are assembled to the first housing  21 , the second lens assembly  32  and first lens assembly  31  are mounted from the upper side of the first housing  21  so that the supporting arm  34   a  and  33   a  are fitted slidably to the first shaft  26   a  and the supporting arms  34   b &#39;s and  33   b &#39;s are fitted slidably to the second shaft  26   b  in the state the upper arm of the arms  34   b &#39;s is located between the arms  33   b &#39;s, then the cylindrical cam is mounted from the upper side of the first housing through inserting the journal  30   e  of the cylindrical cam  30  into the bearing bore of the cam mounting part  27  (see  FIG. 4 ) provided at a peripheral part of the base part of the first housing  21  so that the upper contact face of the cam follower arm  34   c  contacts the zooming face  30   d  and the lower contact face of the cam follower arm  33   c  contacts the zoom focusing face  30   c . With this construction, the contact positions of the cam follower arms  33   c  and  34   c  with the zoom focusing face  30   c  and zooming face  30   d  of the spiral formation  30   b  move along the faces  30   c  and  30   d  respectively as the cylindrical cam rotates, and the first and second lens assemblies can be moved smoothly in the direction of the optical axis guided by the first and second shafts  26   a  and  26   b.    
      As the lens holder  34  is provided with the depressions  34   d &#39;s as shown in  FIG. 9  and  FIG. 10  so that it can advance into the space surrounded by the annular formation  22   a  without interfered by the protrusions (on which are defined the reference surfaces  22   b &#39;s) of the annular formation  22   a  in the opening  22  shown in  FIG. 3 , the lens holder  34  can be moved near to the fixed lens retained in the opening  22 . Therefore, a camera module can be provided which has zoom ratio large enough by securing enough moving distance of the lens holder  34 . As the cutout opening part  11   a  is provided in the casing  11  as shown in  FIG. 1 , lens moving mechanism  13  such as lens holders  33 ,  34 , and cylindrical cam  30  are accessible from outside before the opening part is covered, it is possible to perform visual inspection, a variety of adjustment, and accuracy confirmation of the optical system.  
      The driving motor (stepping motor, for example)  38  composing the lens moving mechanism  13  having the gear  38   a  attached to the motor shaft thereof is supported on the supporting face  41   a  of the second housing  41  with the gear-side down and the gear  38   a  inserted into the opening  41   a  as shown in  FIG. 11 . In this state, the gear  38   a  is located above the third gear  29   c  and meshes with the gear  29   b  shown in  FIG. 8 . Further, one of the branched parts of the flexible band  40  is attached to the boss  39  provided on a peripheral part of the driving motor  38 , and the flexible band  40  is extended out of the second housing  41 .  
      In one of the side wall  41   c  of the second housing  41  is defined the opening  41   f , at which the other of the branched parts of the flexible band  40  mounted with the optical sensor  16  is attached. The optical sensor  16  detects the reference line on the cylindrical part  30   a  of the cylindrical cam  30  to determine the original position of the cylindrical cam  30  or rotation angle position or angles rotated. The flexible band having the optical sensor  16  mounted thereto serves also for covering the opening  41   f . With the construction like this, the motor  38  is mounted at the opening  42  and the sensor  16  is mounted at the opening  41   f  without reducing the strength of the second housing, and a camera module can be constructed to be small in size and light in weight, and to have enough strength, and a portable terminal equipped with the camera module can be provided.  
      The driving motor  38  is attached to the second housing  41  of the casing  11  as shown in  FIG. 12 . The cutout opening  42  is defined in a side wall of the second housing  41  to extend in the vertical direction to be upwardly open. Further, the side wall is thin near the cutout opening  42  of the second housing  41 , and the width of the cutout opening is smaller than the diameter of the driving motor  38 . The depth of the second housing in the plane perpendicular to the direction of the optical direction of the lens holders  33 ,  34  is about the same as the sum of the diameter of the cylindrical cam and the diameter of the driving motor  38 . Therefore, the driving motor  38  and the cylindrical cam  30  can be located to be adjacent to each other in the direction of the depth.  
      In  FIG. 12, 13 , each of the inside surface of both sides of the vertically extending cutout opening  42  is formed into the surface of a segment of a cylinder so that the peripheral surface of the driving motor  38  contacts the surfaces of the cylindrical segments tight fittingly in the state the driving motor  38  is supported on the supporting face  41   a . Therefore, by applying an adhesive agent to the surfaces of the cylindrical segments as shown by hatching in  FIG. 12  and locating the driving motor  38 , the same is adhered and fixed to the second housing  41  firmly. The flexible band  40  is drawn out of the second housing  41  from the upper part of the housing as shown in  FIG. 13 . The part where the flexible band  40  is drawn out is covered by the cover plate  43  indicated by hatching in  FIG. 13 . The cutout opening part  42  is covered by the light shielding cover plate  42   a  (see  FIG. 14 ).  
      In some cases, the diameter of such a very small motor may be smaller than 5 mm, and it is difficult to attach the motor in such a way as to provide screw holes on the end face of the output shaft side of the motor to fix the motor in the camera module. Therefore, it is a most common way to wind a ring plate around the periphery of the motor and fix the ring plate to the case of the camera module. However, it is difficult to fix the motor in position with good accuracy in position and inclination by such a way. Therefore, as a method of attaching the drive motor in the camera module like this, said method has a problem in accuracy point of view.  
      However, by fixing the driving motor in this way, the driving motor  38  is bonded and fixed to the surfaces of the cylindrical segment defined inside both sides of the vertically extending cutout opening part  42  tight fittingly with good accuracy. Therefore, the driving motor can be fixed easily and simply to the housing with good accuracy without necessity of using fastening screws or ring plate as has been the case with prior arts.  
      In the embodiment, the motor  38  and cylindrical cam  30  are juxtaposed to each other and in the vicinity of the moving lens holders  33 ,  34  of the optical lens system  12  and the center axis of the cylindrical cam  30  is parallel to the optical axis of the lens system  12  as recognized from  FIG. 14 , so that the optical lens system  12 , motor  38 , and cylindrical cam  30  can be incorporated with ease. In addition, as the depth of the second housing  41  in the plane perpendicular to the direction of the optical direction of the lens holders  33 ,  34  is about the same as the sum of the diameter of the cylindrical cam and the diameter of the driving motor  38 , a downsized camera module can be provided.  
      The first housing  21  mounted with the lens system and driving mechanism is joined to the second housing  41  to which the driving motor is fixed such that; a corner part of the base part of the first housing  21  where the bolt hole  46  is provided mates to the boss part  59  of the second housing  41 , the lower end face of the side wall part  41   c  (see  FIG. 11 ) of the second housing  41  mates to the upper end face of the side wall part  21   b  (see  FIG. 5, 6 , and  8 ) of the first housing  21 , and the side end face  44  (see  FIG. 11 ) of the second housing  41  mates to the side end face  45  (see  FIG. 5, 6 , and  8 ) of the first housing  21 . That is, an adhesive agent is applied onto the adhesive-joining part  47  of the first housing  21 , a bolt (not shown in the drawings) is let in through the bolt hole indicated by reference numeral  46  in  FIG. 4 , the side end face  44  (see  FIG. 11 ) of the second housing  41  with the driving motor fixed thereto mates to the side end face  45  (see  FIG. 5, 6 ,  8 ) of the first housing  21 , and the second housing is fixed to the first housing with the bolt and the adhesive agent while preventing deviation of the housings relative to each other in rotational direction around the fixing part  46  to be fixed by the bolt.  
      When the first housing  21  and second housing  41  are joined together and fixed in this way, a board mounted with the CCD indicated by reference numeral  15  is adhered to the image pickup device attaching parts  60   a  and  60   b  of the first and second housing. The attaching of the board mounted with the CCD  15  is performed in such a way that; the board mounted with the CCD  15  is moved around 5 axes, taking for example three points indicated by reference numerals  48 &#39;s as the basis for the movement while picking up an image sent through the optical system  12 , a position of the board is detected with which the optical axis of the CCD  15  and that of the optical lens system  12  coincide and at the same time the image is optimally focused into the CCD  15 , the board is retained in the position, and an adhesive agent is inpoured to the concave  58 . In this way, the board mounted with the CCD  15  is bonded and fixed to the casing  11 .  
      After the board mounted with the CCD  15  is fixed to the casing  11 , the cover plate (light shielding member) indicated by reference numeral  14  in  FIG. 1  is attached by means of an adhesive agent to the casing  11  to cover the cutout opening defined by the first housing  21  and second housing  41 , and the cutout opening part indicated by reference numeral  42  at the attaching part of the driving motor  38  and other cutout opening parts are covered similarly with cover plates (light shielding members) to bring the camera module of the embodiment shown in  FIG. 1  to completion.  
      Although the casing  11  of the camera module of the embodiment has the cutout opening parts  11   a ,  11   b  shown in  FIG. 12 , the opening  41   f  shown in  FIG. 12 , and the cutout opening part  42 , each of the opening parts is covered with the cover plate  14  which covers the opening part  11   a , with the flexible band mounted with the optical sensor  16  which covers the opening  41   f , with the cover plate  41   e  which covers the opening part  11   b , and with the cover plate  42   a  which covers the opening part  42 . As the cover plate  14  covers the opening part between the first thick side wall part  21   a  and the second thick side wall part  21   b , the cover plate  41   e  covers the opening part of the second housing  41  in the state the cover is bent at right angles to form a corner part, the opening  42  is relatively narrow in width, shut up by the motor  38  and covered with the cover plate  42   a , and the opening  41   f  is relatively small and covered with the flexible band, the casing  11  is made strong enough by the presence of those covers. Further, as the cylindrical cam  30  and the lens moving mechanism including lens holders  33 ,  34 , etc. can be accessed through the opening  11   a  before the cover plate  14  is attached, it is possible to perform visual inspection, a variety of adjustment, and accuracy confirmation of the optical system when assembling the camera module. Further, the sliding condition of the lens holders  33 ,  34  can be confirmed from the opening  11   b , and the opening  42  is used for attaching the driving motor  38  as mentioned before. Thus, these opening parts are used effectively and serves to reduce the weight of the camera module.  
      In the camera module of the embodiment constructed like this, when the driving motor  38  shown in  FIG. 11  rotates, the rotation force is transmitted from the gear  38  to the cylindrical cam via the gears  29   a - 29   d  shown in  FIG. 8 . The cam follower arms  33   c  and  34   c  of the first and second lens assembly  31  and  32  are moved in the direction of the optical axis by the rotation of the spiral formation  30   b  of the cylindrical cam  30 , and zooming and focusing can be done smoothly as mentioned before. The original position of the cylindrical cam  30  can be determined through detecting the reference line on the cylindrical part  30   a  by the optical sensor  16 , and focus distance and focus position can be obtained by counting the number of pulses given to the driving motor such as a pulse motor.  
      As has been described in the foregoing, according to the embodiment, by providing concaved portions in the retaining portion for retaining one of the lenses of the optical lens system to allow a lens holder to advance to the retaining portion, a camera module can be provided which is small in size, light in weight, and composed such that lens moving distance of enough length can be secured even if autofocusing function and zooming function are incorporated.  
      In a camera module like this, lenses, a lens moving mechanism such as a cam and motor for autofocusing or zooming, gears, etc. are desirable to be composed of as small number of parts as possible, material of the parts should be carefully selected to achieve long operation life. Also, the order and direction of assembling component parts must be taken into consideration for automatic assembling in order to save man-hours. Further, the casing of simple structure is desired for the camera module for cost reduction.  
      In the case the driving mechanism and driving source for moving lenses and gears for transmitting the driving force of the driving source to the driving mechanism are incorporated in the camera module, the casing of the camera module must be composed to be strong enough to retain them positively, and normal photographic image can not be obtained if the camera module is not perfectly shielded from intrusion of light.  
      However, in the camera module of the embodiment, as the shaft made of resin is molded in one piece with the housing as has been mentioned in the forgoing, the number of constituent parts is reduced and man-hours to attach the shaft are eliminated. Further, as fluorine is contained in the material of the housing, the housing can be produced to have enough strength.  
      Further, as the reference points (surfaces)  23 &#39;s are provided on the basis of the reference surfaces  22   b &#39;s for retaining the fixed lens, and the lens assemblies comprising the holders  33 ,  34 , and the lens moving mechanism comprising the cylindrical cam  30  and gears  29   a ˜ 29   d  can be assembled from opened side of the housing, the assembling and adjusting of the optical lens system  12  and the lens moving mechanism can be performed with ease and they can be automated retaining good accuracy. Further, when molding, the first housing  21  can be drawn out of the mold in one direction with accuracy secured in the side where both reference surfaces are formed and the housing can be produced at a low cost.  
      Further, as the annular formation, on which reference surfaces  22   b &#39;s for determining the position of the object side fixed lens in the optical axis are defined, is formed in the opening for attaching the object side fixed lens of the first housing  21 , and at least three salient parts are provided on the inside surface of the opening for attaching the fixed lens above the annular formation such that the periphery of the lens contacts the salient parts, the fixed lens can be positioned accurately in relation to the direction of the optical axis.  
      Further, as the driving motor  38  is fixed to the second housing adjacent the cylindrical cam  30 , and the depth of the second housing in a plane perpendicular to the optical axis of lens system is about the same as the sum of the diameter of the cylindrical cam  30  and the diameter of the driving motor  38 , the camera module can be constructed to be small in size.  
      Further, as the cylindrical surface to which the driving motor  38  is bonded with its periphery is formed such that the cutout opening part  42  is formed and the side wall becomes thin near the opening part, and the opening part is covered with the light shielding member  42   a , the motor attaching part of the second housing can be formed to be thin-walled and the camera module can be constructed to be very small in size.  
      The width of the cutout opening part  42  is smaller than the diameter of the driving motor  38 , and each of the inside surface of both sides of the opening part  42  is formed into the surface of a segment of a cylinder so that the peripheral surface of the driving motor  38  closely contacts the surfaces of the cylindrical segments, the motor can be fixed to the second housing with good accuracy.  
      As rotation speeds of the gears fitted rotatably to the metal shafts  26   c ,  26   d  are high but loads are light, shafts of small diameter can be adopted for metal shafts of  26   c ,  26   d , as a result the gears can be small sized, the apparatus (camera module) can be produced to be small in size, and mechanical noise can be reduced. As the rotation speed of the last stage gear  29   d  fitted rotatably to the shaft  28  made of resin is low, noise emission due to the rotation is minimal, and as the shaft  28  is made of resin material, the shaft is light in weight even when the diameter is increased to secure strength. Further, by molding the resin shaft in one piece with the housing, the number of constituent parts is reduced and man-hours to attach the shaft are eliminated.  
      Further, as the casing  11  of the camera module is made of resin containing fluorine, durability and sliding property is increased, and if a shaft and bearing are formed in one piece with the housing, they have high durability and the gear fitted rotatably to the shaft can rotate smoothly. Further, by adopting resin material containing fluorine not a simple resin for the casing, the casing can be increased in strength, as a result the casing can be formed thinner, and downsizing and weight saving of the camera module can be realized.  
      Further, by making the cylindrical cam  30  of resin, or resin containing fluorine, the cam is reduced in weight as compared to the case the cam is made of metal, and by adding fluorine to the resin material, the strength and durability of the cam is increased and the sliding property of the journal  30   e  which rotates in the bearing is improved.  
      Further, the lens holders  33 ,  34  retaining the moving lenses are formed such that; the cam follower arms  33   c ,  34   c  which contact the upper and lower cam faces of the spiral formation of the cylindrical cam respectively, and the supporting arms  33   a ,  33   b &#39;s,  34   a , and  34   b &#39;s each having a groove or hole to be fitted slidably to the guide shafts  26   a ,  26   b  to be guided in the direction of the optical axis, are formed integrally with the lens holders  33 ,  34  respectively to extend radially from the peripheral part of each of the lens holders  33 ,  34 , the supporting arms  33   a  and  34   a  extending in substantially opposite direction to the arms  33   b &#39;s and  34   b &#39;s respectively, the arms  33   b &#39;s and  34   b &#39;s forming a pair of arms respectively, the pair of arms  33   b &#39;s and the pair of arms  34   b &#39;s extending in the direction different by a certain angles θ to the direction of the cam follower arms  33   c  and  34   c  respectively, and the pairs of the arms  33   b &#39;s,  34   b &#39;s are fitted slidably to one of the guide shafts so that one of the pair of the arms  33   b  and one of the pair of the arms  34   b  are fitted slidably to the guide shafts to cross each other in the direction of the optical axis, so that the distance between both arms of the pair of arms can be increased in a narrow space. This allows the camera module to be constructed small in size and effects to reduce the slant of the lens holders  33 ,  34  when the forces to move the lens holders  33 ,  34  exert slanted to the direction of the optical axis.  
      As has been described in the foregoing, according to the embodiment, a camera module having autofocusing and zooming functions and most suitable to incorporate in a portable terminal, etc. can be provided, and a user-friendly portable terminal equipped with the camera module can be provided.