JP2011173303A - Optical head and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To arrange light emitting substrates in a line along a main scanning direction without shortening a distance from a light emitting part at the endmost end to a substrate end part to be a half or less of a light emitting pitch. <P>SOLUTION: The light emitting substrate includes a plurality of first light emitting parts arranged in the main scanning direction, and a second light emitting part arranged in a direction crossing the main scanning direction with respect to arrangement of the plurality of the first light emitting parts. A lens array includes a plurality of first lenses arranged opposite to the plurality of the first emitting parts, and a second lens arranged opposite to the second light emitting part. The respective first lenses image the projection light from the opposed first light emitting part in a position where a straight line connecting the first lens and the first light emitting part opposed to it crosses a surface to be irradiated. The second lens images the projection light from the second light emitting part on the side opposite from a second imaging position with a first imaging position held therebetween when the imaging position of the projection light from the first light emitting part positioned on one end of the plurality of the first light emitting parts is the first imaging position and the imaging position of the projection light from any of other first light emitting parts is the second imaging position. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical head including a plurality of light emitting units and an electronic apparatus.

  An image forming apparatus such as a printer includes an optical head that exposes an image carrier (for example, a sensitive drum) to write a latent image. This type of optical head has a light emitting element array in which a large number of light emitting elements are arranged along the main scanning direction. The light emitting element array is configured by arranging a plurality of light emitting element chips in which a predetermined number of light emitting elements are arranged in the main scanning direction.

  By the way, when a plurality of light emitting element chips are arranged in a line in the main scanning direction, the light emitting pitch is kept constant even at the boundary part between the adjacent light emitting element chips. It was necessary to make the distance up to half or less of the light emission pitch. However, if the distance from the end of the light emitting element to the end of the chip is less than half of the light emission pitch, when the light emission pitch is reduced to increase the resolution, the end of the light emitting element is cut off when the light emitting element chip is cut out. Inconvenience occurs. For this reason, there is a technique for arranging a plurality of light emitting element chips in a zigzag pattern along the main scanning direction (see, for example, Patent Documents 1 and 2).

JP 2002-248803 A JP 2008-155458 A

However, when a plurality of light emitting element chips are arranged in a staggered pattern along the main scanning direction, the width of the optical head in the sub scanning direction becomes large.
The present invention has been made in view of the above-described problems. The light emitting substrates are arranged in a line in the main scanning direction even if the distance from the light emitting portion at the end to the end of the substrate is not less than half the light emitting pitch. It is an object to provide an optical head that can be used, and an electronic device using the optical head.

  In order to solve the above-described problems, an optical head according to a first aspect of the present invention includes a plurality of first light emitting units arranged in a main scanning direction, and the main head with respect to the arrangement of the plurality of first light emitting units. A light emitting substrate having a second light emitting part arranged in a direction intersecting the scanning direction and a position facing each of the plurality of first light emitting parts, and the emitted light from the opposing first light emitting part A plurality of first lenses that form an image on an irradiated surface, and a second lens that is provided at a position facing the second light emitting unit and forms an image of light emitted from the second light emitting unit on the irradiated surface. Each of the plurality of first lenses is opposed to a position where a straight line connecting the first lens and the first light emitting portion facing the first lens intersects the irradiated surface. The emitted light from the light emitting unit is imaged, and the second lens includes the plurality of first light emitting units. The imaging position of the emitted light from the first light emitting unit located at one end is set as the first imaging position, and the imaging position of the emitted light from any one of the first light emitting units is set as the second imaging position. When the image position is set, the emitted light from the second light emitting unit is imaged on the side opposite to the second image forming position with the first image forming position interposed therebetween.

According to this configuration, out of the plurality of first light emitting units arranged on the light emitting substrate, the second light emitting unit is located outside the imaging position of the emitted light from the two first light emitting units located at both ends thereof. Can be imaged. That is, the emitted light from the second light emitting unit is imaged on the irradiated surface outside the positions corresponding to both ends of the plurality of first light emitting units arranged on the light emitting substrate. Therefore, a plurality of light emitting substrates can be arranged in the main scanning direction even if the distance from the light emitting portion at the end to the end of the substrate (hereinafter referred to as the frame portion distance) is not less than half of the light emitting pitch as in the prior art. Since they can be arranged in a line, the width of the optical head in the sub-scanning direction can be reduced and the optical head can be miniaturized.
In addition, according to the present invention, since the distance of the frame portion where the light emitting substrates can be arranged in a line can be made larger than before, the accuracy required when cutting out the light emitting substrate does not have to be as high as before. . For this reason, it becomes easy to cut out the light emitting substrate.

In the optical head according to the first aspect described above, each of the plurality of first lenses has an optical center and a geometric center that coincide with each other, and the first light emitting unit and the first lens that face each other are The light emission center of the first light emitting unit coincides with the optical axis of the first lens, the second lens has an optical center and a geometric center different from each other, and light emitted from the second light emitting unit is emitted from the first light emitting unit. A configuration may be adopted in which the degree of eccentricity is determined so that the image is formed on the side opposite to the second image forming position with the image forming position interposed therebetween.
In this case, a so-called decentered lens (a lens having a different optical center and geometric center) can be used as the second lens.

Further, in the optical head according to the first aspect described above, each of the plurality of first lenses and the second lens has an optical center and a geometric center that are coincident with each other, In the first lens, the light emission center of the first light emitting unit coincides with the optical axis of the first lens, and the second light emitting unit and the second lens emit light from the second light emitting unit in the first lens. The light emitting center of the second light emitting unit and the optical axis of the second lens are arranged so as to be shifted so that an image is formed on the side opposite to the second image forming position across one image forming position. It may be a configuration.
In this case, since the lenses arranged in the lens array can be of one type (lens whose optical center coincides with the geometric center), the lens array can be easily manufactured.

In the optical head according to the first aspect described above, the plurality of first light emitting units are arranged in a line at a predetermined pitch in the main scanning direction, and the second lens is projected from the second light emitting unit. The configuration may be such that the incident light is imaged at a position spaced from the first imaging position in the direction opposite to the second imaging position by the predetermined pitch.
In this case, the imaging positions of the emitted light from the first light emitting units can be kept at regular intervals (predetermined pitch), and of course, from the first light emitting unit located at one end of the plurality of first light emitting units. The distance between the imaging position of the emitted light and the imaging position of the emitted light from the second light emitting unit can also be maintained at a predetermined pitch.

In the optical head according to the first aspect described above, the light emitting substrate includes the two second light emitting units, and the lens array is provided at a position facing each of the two second light emitting units. Two second lenses that image the emitted light from the opposing second light emitting part on the irradiated surface, and one of the second lenses emits from the opposing second light emitting part. The incident light is imaged on the opposite side of the second imaging position across the first imaging position, and the other second lens is placed on the other end of the plurality of first light emitting units. When the imaging position of the emitted light from the first light emitting unit located is the third imaging position, and the imaging position of the emitted light from any one of the first light emitting units is the fourth imaging position The light emitted from the opposing second light emitting unit is opposite to the fourth imaging position side with the third imaging position interposed therebetween. It may be configured to image.
According to this configuration, out of the plurality of first light emitting units arranged on the light emitting substrate, the imaging positions of the emitted light from the two first light emitting units located at both ends are arranged on the outside so as to sandwich the both sides. The emitted light from the two second light emitting units can be imaged. In this case, the distance between the frame portions where the light emitting substrates can be arranged in a line can be increased as compared with the configuration including one second light emitting portion and one second lens.

An optical head according to a second aspect of the present invention includes a plurality of first light emitting units arranged in a main scanning direction and a direction intersecting the main scanning direction with respect to the arrangement of the plurality of first light emitting units. A light-emitting substrate having a second light-emitting portion disposed on the first light-emitting portion and a light-emitting substrate provided at a position facing each of the plurality of first light-emitting portions, and forming an image on the irradiated surface from the light emitted from the facing first light-emitting portion A lens array having a plurality of first lenses and a second lens that is provided at a position facing the second light emitting unit and forms an image of light emitted from the second light emitting unit on the irradiated surface. Each of the plurality of first lenses has an optical center and a geometric center that coincide with each other, and the second lens has a different optical center and geometric center.
According to this configuration, a so-called decentered lens (a lens having a different optical center and geometric center) is used as the second lens, so that it is positioned at both ends of the plurality of first light emitting units arranged on the light emitting substrate. Since the light emitted from the second light emitting unit can be imaged outside the imaging position of the light emitted from the two first light emitting units, the optical head according to the first aspect described above The same effect is produced.

An optical head according to a third aspect of the present invention includes a plurality of first light emitting units arranged in a main scanning direction and a direction intersecting the main scanning direction with respect to the arrangement of the plurality of first light emitting units. A light-emitting substrate having a second light-emitting portion disposed on the first light-emitting portion and a light-emitting substrate provided at a position facing each of the plurality of first light-emitting portions, and forming an image on the irradiated surface from the light emitted from the facing first light-emitting portion A lens array having a plurality of first lenses and a second lens that is provided at a position facing the second light emitting unit and forms an image of light emitted from the second light emitting unit on the irradiated surface. In the first light emitting unit and the first lens facing each other, the light emission center of the first light emitting unit and the optical axis of the first lens coincide, and the light emission center of the second light emitting unit and the second lens are aligned. The second light emitting unit and the second lens are arranged so that the optical axis of the lens is deviated. And which is characterized in that.
According to this configuration, by arranging the second light emitting unit and the second lens so that the light emission center of the second light emitting unit and the optical axis of the second lens are shifted, a plurality of first elements arranged on the light emitting substrate are arranged. Since the light emitted from the second light emitting unit can be imaged outside the imaging positions of the light emitted from the two first light emitting units located at both ends of the light emitting units, the above-described operation is performed. The same effect as the optical head according to the first aspect is obtained.

  An optical head according to a fourth aspect of the present invention is provided at a position facing a light emitting substrate having a plurality of light emitting units arranged in a line in the main scanning direction and each of the plurality of light emitting units. And a lens array having a plurality of lenses that image the emitted light from the light emitting unit on the irradiated surface, and each of the plurality of lenses faces as the arrangement position of the lenses changes from the center to the end. The angle at which the light emitted from the light emitting portion is refracted in the direction from the center toward the end is increased.

  According to this configuration, on the irradiated surface, two light emitting units located at least at both ends of the plurality of first light emitting units outside the positions corresponding to both ends of the plurality of light emitting units arranged on the light emitting substrate. The emitted light from is imaged. Therefore, the same effect as the optical head according to the first aspect described above can be obtained. In addition, in the optical head according to the first aspect described above, the distance between the frame portions where the light emitting substrates can be arranged in a row is increased as compared with the configuration including one each of the second light emitting portion and the second lens. Can do.

In the optical head according to the fourth aspect described above, the plurality of light emitting units are arranged in a line at a first pitch in the main scanning direction, and the plurality of lenses are provided from each of the plurality of light emitting units. The emitted light may be configured to form an image in a line in the main scanning direction at a second pitch larger than the first pitch.
In this case, the imaging positions of the light emitted from the light emitting units can be kept at regular intervals (second pitch).

In the optical head according to the fourth aspect described above, each of the plurality of lenses has a different optical center and geometric center, and the degree of eccentricity increases as the arrangement position of the lenses changes from the center to the end. It may be a configuration.
In this case, a so-called eccentric lens (a lens having a different optical center and geometric center) can be used as the lens arranged in the lens array.

In the optical head according to the fourth aspect described above, each of the plurality of lenses has an optical center and a geometric center that coincide with each other, and the light emitting unit and the lens that face each other have an arrangement position of the lenses. A configuration may be adopted in which the deviation between the light emission center of the light emitting unit and the optical axis of the lens increases from the center to the end.
In this case, a lens in which the optical center and the geometric center coincide can be used as the lens arranged in the lens array.

  The optical head according to any one of the aspects described above may include a plurality of the light emitting substrates and the lens arrays, and the plurality of light emitting substrates and the lens arrays are arranged in the main scanning direction.

The optical head according to each of the above aspects is used for various electronic devices. A typical example of the electronic apparatus according to the present invention is an image forming apparatus. The image forming apparatus includes an optical head according to any one of the above-described embodiments, an image carrier (for example, a photosensitive drum) on which a latent image is formed by exposure by the optical head, and a developer (for example, a latent image on the image carrier) And a developing unit that forms a visible image by adding toner.
However, the use of the optical head according to the present invention is not limited to the exposure of the image carrier. For example, in an image reading apparatus such as a scanner, the optical head according to the present invention can be used for illuminating a document. This image reading apparatus includes an optical head according to any one of the above-described aspects, and a light receiving device (for example, a CCD (Charge Coupled Device) element that converts light emitted from the optical head and reflected by a reading target (original) into an electrical signal. Light receiving element).

1 is a perspective view illustrating a partial structure of an image forming apparatus. 1 is a perspective view showing a structure of an optical head 1 according to a first embodiment. It is sectional drawing which shows the arrangement | positioning relationship between the light emitting element E1 and micro lens ML1. It is sectional drawing which shows the arrangement | positioning relationship between the light emitting element E8 and micro lens ML8. It is a perspective view which shows the structure of the optical head 2 which concerns on 2nd Embodiment. It is sectional drawing which shows the arrangement | positioning relationship between the light emitting element E8 and micro lens ML18. It is a perspective view which shows the structure of the optical head 3 which concerns on 3rd Embodiment. It is sectional drawing which shows the arrangement | positioning relationship between the light emitting element E4 and the micro lens ML24. It is sectional drawing which shows the arrangement | positioning relationship between the light emitting element E6 and the micro lens ML26. 10 is a perspective view showing a structure of an optical head 4 according to Modification Example 5. FIG. It is sectional drawing which shows the specific example (image forming apparatus) of an electronic device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the ratio of dimensions of each part is appropriately different from the actual one.

<A. First Embodiment>
FIG. 1 is a perspective view showing a partial structure of the image forming apparatus.
As shown in the figure, the image forming apparatus includes a photosensitive drum 70 and an optical head 1 that exposes the outer peripheral surface of the photosensitive drum 70 to write a latent image. The optical head 1 includes a light emitting panel 10 in which a plurality of light emitting elements are arranged, and a lens array 20 disposed between the light emitting panel 10 and the photosensitive drum 70. The photosensitive drum 70 is supported by a rotation shaft extending in the X direction (main scanning direction), and rotates with the outer peripheral surface facing the optical head 1. Light from each light emitting element of the light emitting panel 10 is imaged on the surface of the photosensitive drum 70 by the lens array 20.

FIG. 2 is a perspective view showing the structure of the optical head 1 according to the first embodiment.
In FIGS. 1 and 2, the positional relationship between the optical head 1 and the photosensitive drum 70 is reversed up and down (Z direction). Two light emitting element chips 12 are arranged in a line along the X direction on the surface of the light emitting panel 10 shown in FIG. In FIG. 2, two light emitting element chips 12 are illustrated for convenience, but three or more light emitting element chips 12 may be arranged in a row.

  In each light emitting element chip 12, eight light emitting elements E1 to E8 having a circular light emitting surface are formed as light sources for surface light emission. Among these, the six light emitting elements E1 to E6 are arranged in a line at a pitch D1 along the X direction. The remaining two light emitting elements E7 and E8 are provided at positions separated from the light emitting elements E1 and E6 by a predetermined distance in the Y direction (sub-scanning direction). That is, in each light emitting element chip 12, six light emitting elements E1 to E6 are arranged at a pitch D1 on a straight line LX1 extending in the X direction, and two on a straight line LX2 parallel to the straight line LX1 at a predetermined interval. The light emitting elements E7 and E8 are arranged. As is clear from FIG. 2, the light emitting elements E7 and E8 are preferably arranged at positions adjacent to the light emitting elements E1 and E6 at the end of the arrangement of the light emitting elements E1 to E6. In the present embodiment, it is not necessary to provide a light emitting element between the light emitting elements E7 and E8 in the X direction. Note that the number of light emitting elements arranged on the straight line LX1 in one light emitting element chip 12 is not limited to six and may be two or more. In the following description, when it is not necessary to distinguish each light emitting element, it is referred to as a light emitting element E.

  Each light emitting element E is, for example, an organic light emitting diode element, and emits light when supplied with current. Although not shown, each light emitting element E has a light emitting layer formed of an organic EL (Electro Luminescent) material, and one electrode and the other electrode sandwiching the light emitting layer. Each light emitting element E is covered with a sealing layer (not shown), and light from each light emitting element E is transmitted through the sealing layer and emitted. For this reason, the sealing layer and the electrode on the sealing layer side are formed of a material having high light transmittance. Moreover, in order to ensure the tolerance margin at the time of cutting out the light emitting element chip | tip 12, the frame part which has the width | variety D3 exists in the both ends (short side side) of each light emitting element chip | tip 12. FIG. The light emitting element E cannot be disposed in the frame portion.

  Next, the lens array 20 shown in FIG. 1 includes two lens array units 22. Each lens array unit 22 is disposed so as to face the light emitting element chip 12 and has a flat substrate formed of a light-transmitting material (for example, glass) as indicated by a dotted line in FIG. Further, eight circular lens portions are respectively formed on the surface on the photosensitive drum 70 side and the surface on the light emitting element chip 12 side of the base, and two lens portions opposed to each other with the base interposed therebetween. One microlens (biconvex lens) is constituted by the base existing between the two. If the three light emitting element chips 12 are arranged in a line, the lens array 20 is constituted by the three lens array units 22.

  Each lens array unit 22 is provided with a microlens ML1 at a position facing the light emitting element E1, a microlens ML2 is provided at a position facing the light emitting element E2, and a microlens ML6 at a position facing the light emitting element E6. Is provided. Further, a micro lens ML7 is provided at a position facing the light emitting element E7, and a micro lens ML8 is provided at a position facing the light emitting element E8. As described above, among the eight microlenses ML1 to ML8 provided in each lens array unit 22, the six microlenses ML1 to ML6 are arranged in a line at the pitch D1 along the X direction, and the remaining two microlenses. ML7 and ML8 are provided at positions separated from the microlenses ML1 and ML6 by a predetermined distance in the Y direction. In the following description, each microlens is referred to as a microlens ML when it is not necessary to distinguish each microlens.

  Although not shown, a spacer for keeping the distance between the light emitting element chip 12 and the lens array unit 22 constant is disposed between the light emitting element chip 12 and the lens array unit 22. The spacer is formed with eight through holes for allowing the light emitted from each light emitting element E to enter the opposing microlens ML. The spacer is formed of a light-shielding member, and suppresses light from the light emitting element E from entering the microlens ML that does not face the light emitting element E.

  Each microlens ML forms an image of light emitted from the facing light emitting element E on the surface of the photosensitive drum 70. In addition, the micro lenses ML1 to ML6 are lenses whose optical center and geometric center coincide with each other, and are arranged with their central axes directed in the Z direction. The micro lenses ML7 and ML8 are lenses (so-called decentered lenses) having different optical centers and geometric centers. Note that the number of microlenses ML provided in one lens array unit 22 is not limited to eight. For example, when 128 light emitting elements E are provided in one light emitting element chip 12, 128 microlenses ML are provided in one lens array unit 22.

FIG. 3 is a cross-sectional view showing the positional relationship between the light emitting element E1 and the microlens ML1.
The micro lens ML1 is a lens whose optical center and geometric center coincide. As shown in the figure, the light emitting element E1 and the microlens ML1 are arranged to face each other so that the light emission center of the light emitting element E1 and the optical axis of the microlens ML1 coincide. Note that the optical axis of the microlens ML1 is a straight line connecting the centers of the two lens portions constituting the microlens ML1. Further, as an example, the microlens ML1 is a gradient index lens having a cylindrical shape, and the refractive index at the central axis (optical axis) is low in the cross section thereof, and the refractive index increases as the distance from the central axis increases. May be high. The microlens ML1 emits light emitted from the light emitting element E1 and incident on the lower lens portion in the drawing from the upper lens portion in the drawing. Further, the emitted light from the light emitting element E1 is imaged at a position on the surface of the photosensitive drum 70 that intersects the optical axis of the microlens ML1. More specifically, a spot region where the light emitted from the light emitting element E1 is imaged is formed around the position of the surface of the photosensitive drum 70 that intersects the optical axis of the microlens ML1.

  Note that the light emitting element E2 and the microlens ML2, the light emitting element E3 and the microlens ML3,..., The light emitting element E6 and the microlens ML6 also have the same arrangement relationship as the light emitting element E1 and the microlens ML1. Accordingly, the light emitted from each of the light emitting elements E1 to E6 is focused on the surface of the photosensitive drum 70 in a line at the pitch D1 along the X direction.

FIG. 4 is a cross-sectional view showing the positional relationship between the light emitting element E8 and the microlens ML8.
The micro lens ML8 is an eccentric lens, and can refract the traveling direction of the emitted light from the light emitting element E8 to the X direction side. For this reason, as shown in FIG. 2, the microlens ML8 can image the outgoing light from the light emitting element E8 on the X direction side from the imaging position of the outgoing light from the light emitting element E6. Further, the microlens ML8 has a decentered degree of lens so that the emitted light from the light emitting element E8 can be imaged on the X direction side by a pitch D1 from the imaging position of the emitted light from the light emitting element E6. . Thus, the role of the microlens ML8 is to refract light emitted from the light emitting element E8 at least in the X direction. Accordingly, the microlens ML8 can achieve the object of the present invention as long as the microlens ML8 has a function of advancing light emitted from the light emitting element E8 in a direction different from the original emission direction.

  The arrangement relationship between the light emitting element E7 and the microlens ML7 is obtained by reversing the X direction of the arrangement relationship between the light emitting element E8 and the microlens ML8. Therefore, as shown in FIG. 2, the microlens ML7 can image the emitted light from the light emitting element E7 on the opposite side to the X direction from the imaging position of the emitted light from the light emitting element E1. Further, the microlens ML7 has a lens eccentricity so that the emitted light from the light emitting element E7 can be imaged on the opposite side to the X direction by a pitch D1 from the imaging position of the emitted light from the light emitting element E1. It has been.

  Note that the microlens ML8 (ML7) according to the present embodiment bends the emitted light from the facing light emitting element E8 (E7) in the X direction (direction opposite to the X direction). In FIG. 2, the light emitting element chip 12 and the lens array unit 22 on the left side in the drawing, and the light emitting element chip 12 and the lens array unit 22 on the right side in the drawing are emitted from the light emitting element E8 of the light emitting element chip 12 on the left side in the drawing. The distance between the image formation position of the emitted light and the image formation position of the light emitted from the light emitting element E7 of the light emitting element chip 12 on the right side in the drawing is arranged to be the pitch D1.

  The optical head 1 includes a drive circuit (not shown) that controls the magnitude of a current supplied to each light emitting element E and the light emission timing of each light emitting element E. This drive circuit controls the magnitude of the current supplied to each light emitting element E according to the image printed on the recording material such as paper. In addition, the driving circuit is configured so that a latent image corresponding to one line of an image is formed on the surface of the photosensitive drum 70 by light emitted from all the light emitting elements E provided in the light emitting panel 10. Control the light emission time.

  Here, when the distance between the straight line LX1 and the straight line LX2 shown in FIG. 2 is ΔD, when the driving circuit causes all the light emitting elements E1 to E6 on the straight line LX1 to emit light, the surface of the photosensitive drum 70 is in the Y direction. Then, after the time required to travel by the distance ΔD elapses, all the light emitting elements E7 and E8 on the straight line LX2 are caused to emit light. As a result, the light emitted from the light emitting element E7 is imaged on the outer peripheral surface of the photosensitive drum 70 at a position separated from the imaging position of the light emitted from the light emitting element E1 by the pitch D1 on the opposite side to the X direction. The Further, the emitted light from the light emitting element E8 is imaged at a position separated from the imaging position of the emitted light from the light emitting element E6 by a pitch D1 in the X direction. Therefore, on the outer peripheral surface of the photosensitive drum 70, the light emitted from all the light emitting elements E provided in the light emitting panel 10 is imaged in a line at a pitch D1 in the X direction, thereby forming one line of a latent image. . Further, by repeating the same operation in parallel with the rotation of the photosensitive drum 70, a latent image composed of a plurality of lines is formed on the outer peripheral surface of the photosensitive drum 70.

  As described above, according to the present embodiment, out of the light emitting elements E1 to E6 arranged in the light emitting element chip 12, the image forming position of the emitted light from the light emitting elements E1 and E6 located at both ends thereof is outside. The emitted light from the light emitting elements E7 and E8 can be imaged while maintaining the pitch D1. That is, the emitted light from the light emitting elements E7 and E8 can be imaged on the surface of the photosensitive drum 70 corresponding to the frame portion of the light emitting element chip 12. Therefore, a plurality of light emitting element chips 12 can be arranged in a line in the X direction without the width D3 of the frame portion being equal to or less than half of the pitch D1 as in the prior art. For example, in the case of FIG. 2, the width D3 of the frame portion where the light emitting element chips 12 can be arranged in a row is a maximum pitch D1 × 1.5. That is, if the width D3 of the frame portion is a pitch D1 × 1.5 or less, the light emitting element chips 12 can be arranged in a line in the X direction.

  Thus, according to this embodiment, even if the frame width D3 is larger than half of the pitch D1, the light emitting element chips 12 can be arranged in a line in the X direction as long as the pitch is D1 × 1.5 or less. Therefore, the width of the optical head 1 in the Y direction can be reduced, and the optical head 1 can be downsized. In addition, according to the present embodiment, the frame width D3 that allows the light emitting element chips 12 to be arranged in a line can be made larger than the conventional one, so that the accuracy required when cutting out the light emitting element chips 12 is improved. It's not as expensive as before. For this reason, the light emitting element chip 12 can be easily cut out.

<B. Second Embodiment>
Next, a second embodiment will be described. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted as appropriate.
FIG. 5 is a perspective view showing the structure of the optical head 2 according to the second embodiment.
The optical head 2 according to this embodiment is different from the optical head 1 of the first embodiment only in the microlenses ML17 and ML18 provided in each lens array unit 24. In the first embodiment, decentered lenses are used as the microlenses ML7 and ML8 facing the light emitting elements E7 and E8. However, in the present embodiment, the microlenses ML17 and ML18 facing the light emitting elements E7 and E8 are optical centers. Use lenses with geometric centers that coincide.

FIG. 6 is a cross-sectional view showing the positional relationship between the light emitting element E8 and the microlens ML18.
The microlens ML18 is a lens in which the optical center and the geometric center coincide with each other, but the optical axis of the lens is arranged to be shifted in the X direction from the light emission center of the light emitting element E8. Therefore, the microlens ML18 can refract the traveling direction of the emitted light from the light emitting element E8 to the X direction side. Further, as shown in FIG. 5, the microlens ML18 forms an image of the outgoing light from the light emitting element E8 on the X direction side with respect to the imaging position of the outgoing light from the light emitting element E6. Further, the microlens ML18 has the optical axis of the lens of the light emitting element E8 so that the emitted light from the light emitting element E8 can be imaged on the X direction side by the pitch D1 from the imaging position of the emitted light from the light emitting element E6. Arranged from the emission center in the X direction.

  The arrangement relationship between the light emitting element E7 and the microlens ML17 is obtained by reversing the X direction of the arrangement relationship between the light emitting element E8 and the microlens ML18. Therefore, as shown in FIG. 5, the microlens ML17 can image the emitted light from the light emitting element E7 on the side opposite to the X direction from the imaging position of the emitted light from the light emitting element E1. The microlens ML17 emits the optical axis of the lens so that the emitted light from the light emitting element E7 can be imaged on the opposite side to the X direction by the pitch D1 from the imaging position of the emitted light from the light emitting element E1. The element E7 is arranged so as to be shifted from the light emission center to the side opposite to the X direction.

  Accordingly, the microlenses ML17 and ML18 function in the same manner as the microlenses ML7 and ML8 in the first embodiment. Therefore, by controlling the light emission timing in the drive circuit as in the first embodiment, the light emitted from the light emitting element E7 is imaged on the outer peripheral surface of the photosensitive drum 70 from the light emitted from the light emitting element E1. The image is formed at a position separated from the position by a pitch D1 on the opposite side to the X direction. Further, the emitted light from the light emitting element E8 is imaged at a position separated from the imaging position of the emitted light from the light emitting element E6 by a pitch D1 in the X direction. Therefore, all the light emitted from the light emitting elements E is imaged in a line at the pitch D1 in the X direction on the outer peripheral surface of the photosensitive drum 70.

  As described above, also in this embodiment, the emitted light from the light emitting elements E7 and E8 is imaged while maintaining the pitch D1 outside the imaging position of the emitted light from the light emitting elements E1 and E6 located at both ends. Can do. Therefore, the same effects as those of the first embodiment are obtained. Further, in the present embodiment, it is not necessary to use an eccentric lens as in the first embodiment, and all the microlenses ML provided in each lens array unit 24 are lenses in which the optical center coincides with the geometric center. Can do. That is, since the microlens ML provided in each lens array unit 24 can be made one type, the lens array 20 can be easily manufactured.

<C. Third Embodiment>
Next, a third embodiment will be described. Also in this embodiment, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted as appropriate.
FIG. 7 is a perspective view showing the structure of the optical head 3 according to the third embodiment.
Each light emitting element chip 16 is obtained by deleting the light emitting elements E7 and E8 from the light emitting element chip 12 of the first embodiment, and six light emitting elements E1 to E6 are arranged in a line at a pitch D1 along the X direction. ing. In each lens array unit 26, microlenses ML21 to ML26 are formed at positions facing the light emitting elements E1 to E6. These six microlenses ML21 to ML26 are lenses in which the optical center coincides with the geometric center, and are arranged in a line along the X direction. Note that the number of pairs of the light emitting element E and the microlens ML facing each other is not limited to six.

FIG. 8 is a cross-sectional view showing the positional relationship between the light emitting element E4 and the microlens ML24. FIG. 9 is a cross-sectional view showing the positional relationship between the light emitting element E6 and the microlens ML26.
As shown in FIGS. 8 and 9, the microlens ML24 (ML26) is arranged such that the optical axis of the lens is shifted in the X direction from the emission center of the light emitting element E4 (E6). Therefore, the microlens ML24 (ML26) can refract the traveling direction of the emitted light from the light emitting element E4 (E6) to the X direction side. Further, the amount of deviation in the X direction between the optical axis of the lens and the light emission center is larger in the microlens ML26 than in the microlens ML24. Therefore, the micro lens ML26 has a larger angle for refracting the emitted light in the X direction side than the micro lens ML24.

  Note that the arrangement relationship between the light emitting element E1 and the microlens ML21 is obtained by reversing the X direction of the arrangement relationship between the light emitting element E6 and the microlens ML26. Also, the arrangement relationship between the light emitting element E3 and the microlens ML23 is obtained by reversing the X direction of the arrangement relationship between the light emitting element E4 and the microlens ML24. Therefore, the microlens ML21 (ML23) is arranged such that the optical axis of the lens is shifted from the light emission center of the light emitting element E1 (E3) to the opposite side to the X direction. Therefore, the microlens ML21 (ML23) can refract the traveling direction of the emitted light from the light emitting element E1 (E3) to the side opposite to the X direction. Further, the amount of deviation in the X direction between the optical axis of the lens and the emission center is larger in the microlens ML21 than in the microlens ML23. Accordingly, the microlens ML21 has a larger angle for refracting the emitted light to the opposite side to the X direction than the microlens ML23.

  As described above, in the microlenses ML24 to ML26, the angles at which the emitted light from the light emitting element E facing each other is refracted in the X direction increases in the order of the microlens ML24 → the microlens ML25 → the microlens ML26. Accordingly, the amount of deviation in the X direction between the optical axis of the lens and the emission center also increases in the order of ML24, E4 → ML25, E5 → ML26, and E6. On the other hand, the angles at which the microlenses ML21 to ML23 refract the emitted light from the facing light emitting element E in the direction opposite to the X direction increase in the order of microlens ML23 → microlens ML22 → microlens ML21. Therefore, the amount of deviation in the X direction between the optical axis of the lens and the emission center also increases in the order of ML23, E3, ML22, E2, ML16, and E1.

  In other words, the microlenses ML21 to ML26 increase the angle at which the emitted light from the opposing light emitting element E is refracted in the direction from the center toward the end as the arrangement position in each lens array unit 26 changes from the center to the end. . Further, the microlenses ML21 to ML26 emit light emitted from the light emitting elements E1 to E6 with respect to the surface of the photosensitive drum 70 in the X direction at a pitch D2 larger than a pitch D1 that is an arrangement interval of the light emitting elements E1 to E6. In order to form an image in a line, the optical axis of the lens is arranged so as to be shifted from the light emission center of the opposing light emitting element E. Accordingly, the light emitted from the light emitting elements E1 to E6 is focused on the surface of the photosensitive drum 70 at a pitch D2 along the X direction. In the present embodiment, since all the light emitting elements E are arranged in a line in the X direction, it is not necessary to shift the light emission timing of each light emitting element E in the drive circuit as in the first embodiment.

  As described above, according to the present embodiment, out of the light emitting elements E1 to E6 arranged in the light emitting element chip 16, the light emitted from the light emitting elements E1 and E6 located at both ends thereof is the surface of the photosensitive drum 70. The image is formed while maintaining the pitch D2 outside the positions corresponding to the light emitting elements E1 and E6. That is, the emitted light from the light emitting elements E1 and E6 can be imaged on the surface of the photosensitive drum 70 corresponding to the frame portion of the light emitting element chip 16. Therefore, the same effects as those of the first embodiment are obtained. Moreover, since it is not necessary to shift the light emission timing of each light emitting element E in the drive circuit as in the first embodiment and the second embodiment, the control configuration of the drive circuit can be simplified.

  In addition, an eccentric lens can be used as the micro lenses ML21 to ML26. When an eccentric lens is used, the degree of eccentricity of the microlenses ML24 to ML26 is determined so that the emitted light from the facing light emitting element E can be refracted in the X direction. Further, the eccentricity of the microlenses ML24 to ML26 increases in the order of the microlens ML24 → the microlens ML25 → the microlens ML26. On the other hand, in the microlenses ML21 to ML23, the degree of eccentricity of the lens is determined so that the emitted light from the facing light emitting element E can be refracted to the side opposite to the X direction. The eccentricity of the microlenses ML21 to ML23 increases in the order of the microlens ML23 → the microlens ML22 → the microlens ML21. When the eccentric lens is used in this way, the degree of eccentricity of each micro lens ML increases so that the arrangement position in the lens array unit 26 increases from the center to the end, and the emitted light from the light emitting elements E1 to E6 is reduced. It is determined so that images can be formed in a line in the X direction at a pitch D2.

<D. Modification>
The present invention is not limited to the above-described embodiments, and for example, the following modifications are possible. Also, two or more modifications shown below can be combined as appropriate.
(Modification 1) In the first embodiment, the positions of the light emitting elements E7 and E8 are not limited to the positions shown in FIG. For example, the positions of the light emitting elements E7 and E8 may be moved closer to the center of the light emitting element chip 12 than the position shown in FIG. The positions where the light emitting elements E7 and E8 are provided in this way may be any place other than the frame portion and different from the position on the straight line LX1. However, it is necessary to change the position and eccentricity of the microlenses ML7 and ML8 according to the positions of the light emitting elements E7 and E8. Further, as shown in FIG. 2, it is not necessary to greatly bend the traveling direction of the emitted light when the light emitting elements E7 and E8 are provided as close to both ends of the light emitting element chip 12 as possible (excluding the frame portion). . The above content is the same also about 2nd Embodiment.

(Modification 2) In the first embodiment, the microlens ML8 (eccentric lens) can refract light emitted from the light emitting element E8 not only in the X direction but also in a direction opposite to the Y direction. There may be. In this case, the degree of eccentricity of the microlens ML8 is determined so that the emitted light from the light emitting element E8 can be imaged at a position spaced apart by the pitch D1 in the X direction from the imaging position of the emitted light from the light emitting element E6. Good. The same applies to the microlens ML7. In other words, the microlens ML7 decenters the lens so that the emitted light from the light emitting element E7 can be imaged at a position spaced apart from the imaging position of the emitted light from the light emitting element E1 by a pitch D1 opposite to the X direction. The degree may be determined. If the eccentricities of the microlenses ML7 and ML8 are determined in this way, it is not necessary to shift the light emission timing between the light emitting elements E1 to E6 and the light emitting elements E7 and E8, so that the control configuration of the drive circuit can be simplified.
The same applies to the microlenses ML17 and ML18 in the second embodiment. However, in the case of the second embodiment, the amount of deviation between the optical axis of the lens and the light emission center is adjusted in the direction opposite to the Y direction instead of the eccentricity.

(Modification 3) In the first embodiment, when a plurality of sets of light emitting element chips 12 and lens array units 22 are arranged in a line in the X direction, the set of light emitting element chips 12 and lens array units 22 located at both ends thereof is Only one side is adjacent to the other. Therefore, for example, among the two sets of the light emitting element chip 12 and the lens array unit 22 shown in FIG. 2, the light emitting element chip 12 and the light emitting element E7 and the microlens ML7 in the left side in the figure, and the right side in the figure. The light emitting element E8 and the microlens ML8 in the light emitting element chip 12 and the lens array unit 22 may be omitted. Further, the light emitting element E7 and the microlens ML7 (or the light emitting element E8 and the microlens ML8) may not be provided in all of the plurality of sets of the light emitting element chips 12 and the lens array unit 22 arranged in a line.
For example, when the light emitting element E7 and the microlens ML7 (or the light emitting element E8 and the microlens ML8) are eliminated in the configuration shown in FIG. 2, the width D3 of the frame portion where the light emitting element chips 12 can be arranged in a row is maximum. Is the pitch D1. That is, if the width D3 of the frame portion is equal to or less than the pitch D1, the light emitting element chips 12 can be arranged in a line in the X direction. The above content is the same also about 2nd Embodiment.

(Modification 4) For example, in each light emitting element chip 12 shown in FIG. 2, a total of four light emitting elements E are provided on the straight line LX2, two on one side, and the imaging positions of the emitted light from the light emitting elements E1 and E6 Further, the configuration may be such that the emitted light from the four light emitting elements E is imaged on the outer side. With such a configuration, the width D3 of the frame portion that allows the light emitting element chips 12 to be arranged in a row can be increased. However, when the number of light emitting elements E on the straight line LX2 is increased in this way, it is necessary to increase the number of microlenses ML (eccentric lenses). Further, it is necessary to adjust the eccentricity of the microlens ML so that the emitted light from each light emitting element E on the straight line LX2 can be imaged while maintaining the pitch D1. The same applies to the second embodiment. However, in the case of the second embodiment, the amount of deviation between the optical axis of the lens and the emission center is adjusted instead of the eccentricity.
Also in the case of the third embodiment, the position corresponding to the light emitting elements E1 and E6 on the surface of the photosensitive drum 70 is adjusted by adjusting the amount of deviation between the optical axis of the lens and the emission center and the degree of eccentricity of the lens. It is possible to increase the number of light-emitting elements E that form an image on the outer side, thereby making it possible to increase the width D3 of the frame portion where the light-emitting element chips 16 can be arranged in a line.

(Modification 5) In the first embodiment, the case where one light emitting element E is arranged in the Y direction from each end of the light emitting elements E1 to E6 as shown in FIG. 2 is described, but as shown in FIG. Two light emitting elements E may be arranged in the Y direction from both ends of the light emitting elements E1 to E6.
FIG. 10 is a perspective view showing the structure of the optical head 4 according to the fifth modification.
In each light-emitting element chip 18, in addition to the eight light-emitting elements E1 to E8 described in the first embodiment, light-emitting elements E9 and E10 are arranged at positions spaced from the light-emitting elements E7 and E8 by a predetermined distance in the Y direction. The In FIG. 10, the interval between the straight lines LX1 and LX2 and the interval between the straight lines LX2 and LX3 are not necessarily the same. In addition to the eight microlenses ML1 to ML8 described in the first embodiment, each lens array unit 28 is provided with a microlens ML9 at a position facing the light emitting element E9, and a microlens at a position facing the light emitting element E10. A lens ML10 is provided. The micro lenses ML9 and ML10 are eccentric lenses. The microlens ML9 has a degree of lens eccentricity so that the emitted light from the light emitting element E9 can be imaged on the opposite side to the X direction by a pitch D1 from the imaging position of the emitted light from the light emitting element E7. Yes. The microlens ML10 has a degree of lens eccentricity so that the emitted light from the light emitting element E10 can be imaged on the X direction side by a pitch D1 from the imaging position of the emitted light from the light emitting element E8. . The microlens ML9 only needs to be able to refract light emitted from the light emitting element E9 at least on the side opposite to the X direction, but refract light emitted from the light emitting element E9 also on the side opposite to the Y direction. Can do. Similarly, the microlens ML10 only needs to be able to refract the emitted light from the light emitting element E10 at least in the X direction, but can also refract the emitted light from the light emitting element E10 to the side opposite to the Y direction. Even in the optical head 4 having such a configuration, the light emitted from the four light emitting elements E7 to E10 is kept at the pitch D1 outside the imaging position of the light emitted from the light emitting elements E1 and E6. An image can be formed in a line. Further, the width D3 of the frame portion where the light emitting element chips 18 can be arranged in a line can be set to a maximum pitch D1 × 2.5. Note that three or more light emitting elements E may be arranged in the Y direction from both ends of the light emitting elements E1 to E6. Of course, when the number of light emitting elements E arranged in the Y direction is increased, it is necessary to increase the number of microlenses ML (eccentric lenses). Further, it is necessary to adjust the eccentricity of the microlens ML so that the emitted light from the light emitting elements E arranged in the Y direction can be imaged while maintaining the pitch D1.

  Moreover, the above content is the same also about 2nd Embodiment. However, in the case of the second embodiment, the microlenses ML7 to ML10 in FIG. 10 are not decentered lenses but lenses whose optical centers and geometric centers coincide. Therefore, for the microlenses ML7 to ML10 and the light emitting elements E7 to E10, it is necessary to adjust the shift amount between the optical axis of the lens and the light emission center. That is, in the case of the configuration shown in FIG. 10, the microlens ML7 and the light emitting element E7 and the microlens ML8 and the light emitting element E8 are the same as the microlens ML17, the light emitting element E7, the microlens ML18, and the light emitting element E8 in the second embodiment. Although not described, the microlens ML9 can image the emitted light from the light emitting element E9 on the opposite side to the X direction by a pitch D1 from the imaging position of the emitted light from the light emitting element E7. The optical axis of the lens is shifted from the light emission center of the light emitting element E9 at least on the side opposite to the X direction. Further, the microlens ML10 has the optical axis of the lens of the light emitting element E10 so that the emitted light from the light emitting element E10 can be imaged on the X direction side by the pitch D1 from the imaging position of the emitted light from the light emitting element E8. It is arranged to be shifted from the emission center at least in the X direction.

(Modification 6) In the first embodiment, the lens array 20 may not have a separate base for each lens array unit 22. That is, the lens array 20 has one base provided at a position facing the plurality of light emitting element chips 12, and among the bases, there are eight micros in each region facing each of the plurality of light emitting element chips 12. A lens ML may be provided. In addition, the lens array 20 may have a configuration in which a gap other than a portion where the microlenses ML are arranged is filled with a light-shielding resin or the like. The above contents are the same for the second embodiment and the third embodiment.

(Modification 7) In the first embodiment, the microlenses ML1 to ML6 and the microlenses ML7 and ML8 may have the same or different curvature radii. In addition, if the curvature radius of the lens part of microlens ML7, ML8 is enlarged, the emitted light from the light emitting elements E7, E8 which oppose can be refracted more largely. The same applies to the second embodiment.
In the third embodiment, each of the micro lenses ML21 to ML26 may have the same or different radius of curvature of the lens portion. In addition, the emitted light from the light emitting element E which opposes can be largely refracted, so that the curvature radius of a lens part is large. Accordingly, in each lens array unit 26, the radius of curvature of the lens portion is preferably increased as the arrangement position of the microlenses ML is shifted from the center to the end (ML23 → ML22 → ML21, ML24 → ML25 → ML26).

(Modification 8) The microlenses ML17 and ML18 in the second embodiment may have different radii of curvature between the lens portion on the incident side and the lens portion on the output side. For example, the radius of curvature of the lens part on the exit side can be made smaller than the radius of curvature of the lens part on the incident side. The same applies to the case where a lens whose optical center and geometric center coincide with each other in the third embodiment.

(Modification 9) The light emitting element E is not limited to an organic light emitting diode element, but may be an LED element, an inorganic EL element, a plasma display element, or the like. The light-emitting element E may be a voltage-driven element that is driven by application of a voltage. Further, when the light emitting surface of the light emitting element E has a shape other than circular, the center of gravity may be the light emitting center of the light emitting element E. Further, the pitch D1 and the pitch D2 are not necessarily constant (equal intervals). Further, the light emitting panel 10 may be a bottom emission type instead of a top emission type.

(Modification 10) For example, as described in FIG. 8 of Japanese Patent Application Laid-Open No. 2008-93882, a plurality of light emitting elements E are provided at positions facing one microlens ML. Two light emitting units may be configured. In this case, the center (center of gravity) of the plurality of light emitting elements E constituting one light emitting unit may be used as the light emission center of the light emitting unit.

<E. Electronic equipment>
Next, specific examples of electronic devices using the optical head according to the above-described embodiments and modifications will be described.
FIG. 11 is a cross-sectional view illustrating a configuration of the image forming apparatus.
This image forming apparatus is a tandem type full-color image forming apparatus, and uses the optical head according to the above-described embodiment and modification as an exposure apparatus. The image forming apparatus includes four optical heads 100 (100K, 100C, 100M, and 100Y) and four photosensitive drums 70 (70K, 70C, 70M, and 70Y) corresponding to each optical head 100. One optical head 100 is disposed so as to face the outer peripheral surface of the photosensitive drum 70 corresponding to the optical head 100. Note that the subscripts “K”, “C”, “M”, and “Y” of each symbol are used to form each visible image of black (K), cyan (C), magenta (M), and yellow (Y). Means.

  An endless intermediate transfer belt 72 is wound around the driving roller 711 and the driven roller 712. The four photosensitive drums 70 are arranged around the intermediate transfer belt 72 at a predetermined interval from each other. Each photosensitive drum 70 rotates in synchronization with driving of the intermediate transfer belt 72. In addition to the optical head 100, a corona charger 731 (731K, 731C, 731M, 731Y) and a developing device 732 (732K, 732C, 732M, 732Y) are disposed around each photosensitive drum 70. The corona charger 731 uniformly charges the outer peripheral surface of the corresponding photosensitive drum 70. Each of the optical heads 100 exposes the charged outer peripheral surface to form an electrostatic latent image. Each developing device 732 forms a visible image (visible image) on the photosensitive drum 70 by attaching a developer (toner) to the electrostatic latent image.

  As described above, the visible images of the respective colors (black, cyan, magenta, yellow) formed on the photosensitive drum 70 are sequentially transferred (primary transfer) to the surface of the intermediate transfer belt 72 to form a full-color visible image. Is done. Four primary transfer corotrons (transfer devices) 74 (74K, 74C, 74M, and 74Y) are arranged inside the intermediate transfer belt 72. Each primary transfer corotron 74 electrostatically attracts a visible image from the corresponding photosensitive drum 70, thereby developing a visible image on the intermediate transfer belt 72 that passes through the gap between the photosensitive drum 70 and the primary transfer corotron 74. Transcript.

  The sheets (recording material) 75 are fed one by one from the paper feed cassette 762 by the pickup roller 761 and conveyed to the nip between the intermediate transfer belt 72 and the secondary transfer roller 77. The full-color visible image formed on the surface of the intermediate transfer belt 72 is transferred (secondary transfer) to one side of the sheet 75 by the secondary transfer roller 77 and is fixed to the sheet 75 by passing through the fixing roller pair 78. . The paper discharge roller pair 79 discharges the sheet 75 on which the visible image is fixed through the above steps.

  Since this image forming apparatus uses an organic light emitting diode element as a light source, the apparatus is made smaller than a configuration using a laser scanning optical system. Note that the optical head 100 can also be applied to an image forming apparatus having a configuration other than those exemplified above. For example, a rotary developing type image forming apparatus, an image forming apparatus that directly transfers a visible image from a photosensitive drum 70 to a sheet without using an intermediate transfer belt, or an image that forms a monochrome image. The optical head 100 can also be used for the forming apparatus.

  The use of the optical head 100 is not limited to the exposure of the image carrier. For example, the optical head 100 is employed in an image reading apparatus as an illumination device that irradiates light to a reading target such as a document. Examples of this type of image reading apparatus include a scanner, a copying unit of a copying machine or a facsimile, a barcode reader, or a two-dimensional image code reader that reads a two-dimensional image code such as a QR code (registered trademark).

DESCRIPTION OF SYMBOLS 1-4 ... Optical head, 10 ... Light emitting panel, 12, 16, 18 ... Light emitting element chip, E1-E10 ... Light emitting element, 20 ... Lens array, 22, 24, 26, 28 ... Lens array unit, ML1-ML10, ML17, ML18, ML21 to ML26... Micro lens, 70.

Claims (13)

A light emitting substrate having a plurality of first light emitting units arranged in a main scanning direction, and a second light emitting unit arranged in a direction intersecting the main scanning direction with respect to the arrangement of the plurality of first light emitting units;
A plurality of first lenses, which are provided at positions facing each of the plurality of first light emitting units and form an image of emitted light from the facing first light emitting unit on an irradiated surface, and are opposed to the second light emitting unit. And a lens array having a second lens that forms an image of the emitted light from the second light emitting unit on the irradiated surface,
Each of the plurality of first lenses includes:
The emitted light from the opposed first light emitting unit is imaged at a position where a straight line connecting the first lens and the first light emitting unit facing the first lens intersects the irradiated surface;
The second lens is
The imaging position of the emitted light from the first light emitting part located at one end of the plurality of first light emitting parts is defined as a first imaging position, and the emitted light from any one of the first light emitting parts. When the image forming position is the second image forming position, the light emitted from the second light emitting unit is imaged on the side opposite to the second image forming position across the first image forming position. An optical head characterized by that. Each of the plurality of first lenses has an optical center coincident with a geometric center,
In the first light emitting unit and the first lens facing each other, the light emission center of the first light emitting unit coincides with the optical axis of the first lens,
The second lens is
The optical center is different from the geometric center,
The degree of eccentricity is determined so that light emitted from the second light emitting unit is imaged on the opposite side of the second imaging position across the first imaging position. Item 4. The optical head according to Item 1. In each of the plurality of first lenses and the second lens, an optical center and a geometric center coincide with each other,
In the first light emitting unit and the first lens facing each other, the light emission center of the first light emitting unit coincides with the optical axis of the first lens,
The second light emitting unit and the second lens are
The light emission center of the second light emitting part and the first light emitting part are formed so that the emitted light from the second light emitting part is imaged on the opposite side of the second image forming position across the first image forming position. The optical head according to claim 1, wherein the optical axes of the two lenses are shifted from each other. The plurality of first light emitting units are arranged in a line at a predetermined pitch in the main scanning direction,
The second lens forms an image of the emitted light from the second light emitting unit at a position spaced apart from the first imaging position in the direction opposite to the second imaging position by the predetermined pitch. The optical head according to any one of claims 1 to 3, wherein the optical head is provided. The light emitting substrate has two of the second light emitting units,
The lens array is provided at a position facing each of the two second light emitting units, and has two second lenses that image the emitted light from the opposed second light emitting units on the irradiated surface. And
One of the second lenses is
The emitted light from the opposing second light emitting unit is imaged on the opposite side of the second imaging position with the first imaging position in between,
The other second lens is
The imaging position of the emitted light from the first light emitting part located at the other end of the plurality of first light emitting parts is defined as a third imaging position, and the emitted light from any one of the first light emitting parts. When the image forming position is the fourth image forming position, the light emitted from the opposing second light emitting unit is coupled to the opposite side of the fourth image forming position across the third image forming position. The optical head according to claim 1, wherein the optical head is imaged. A light emitting substrate having a plurality of first light emitting units arranged in a main scanning direction, and a second light emitting unit arranged in a direction intersecting the main scanning direction with respect to the arrangement of the plurality of first light emitting units;
A plurality of first lenses, which are provided at positions facing each of the plurality of first light emitting units and form an image of emitted light from the facing first light emitting unit on an irradiated surface, and are opposed to the second light emitting unit. And a lens array having a second lens that forms an image of the emitted light from the second light emitting unit on the irradiated surface,
Each of the plurality of first lenses has an optical center coincident with a geometric center,
The optical head of the second lens, wherein an optical center and a geometric center are different. A light emitting substrate having a plurality of first light emitting units arranged in a main scanning direction, and a second light emitting unit arranged in a direction intersecting the main scanning direction with respect to the arrangement of the plurality of first light emitting units;
A plurality of first lenses, which are provided at positions facing each of the plurality of first light emitting units and form an image of emitted light from the facing first light emitting unit on an irradiated surface, and are opposed to the second light emitting unit. And a lens array having a second lens that forms an image of the emitted light from the second light emitting unit on the irradiated surface,
In the first light emitting unit and the first lens facing each other, the light emission center of the first light emitting unit coincides with the optical axis of the first lens,
The optical head, wherein the second light emitting unit and the second lens are arranged so that a light emission center of the second light emitting unit and an optical axis of the second lens are shifted. A light emitting substrate having a plurality of light emitting portions arranged in a line in the main scanning direction;
A lens array provided at a position facing each of the plurality of light emitting units, and having a plurality of lenses for imaging light emitted from the facing light emitting units on an irradiated surface;
Each of the plurality of lenses is
The optical head is characterized in that the angle at which the emitted light from the facing light emitting section is refracted in the direction from the center toward the end increases as the arrangement position of the lens moves from the center to the end. The plurality of light emitting units are arranged in a line at a first pitch in the main scanning direction,
9. The light according to claim 8, wherein the plurality of lenses image light emitted from each of the plurality of light emitting units in a row in the main scanning direction at a second pitch larger than the first pitch. head. Each of the plurality of lenses is
The optical center is different from the geometric center,
The optical head according to claim 8, wherein the degree of eccentricity increases as the arrangement position of the lenses changes from the center to the end. Each of the plurality of lenses has an optical center coincident with a geometric center,
The light emitting unit and the lens facing each other have a larger deviation between the light emission center of the light emitting unit and the optical axis of the lens as the arrangement position of the lenses is shifted from the center to the end. 9. The optical head according to 9. 12. The optical head according to claim 1, comprising a plurality of the light emitting substrates and the lens arrays, wherein the plurality of light emitting substrates and the lens arrays are arranged in the main scanning direction. An electronic apparatus comprising the optical head according to claim 1.

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