Light emitting panel, optical print head, and image forming apparatus

In general, according to the embodiment, a light emitting panel includes a glass substrate, a light emitting element, metal wiring, and a mark. The glass substrate allows light to pass through. The light emitting element is present in any one of a first plane and a second plane which is a rear surface of the first plane, of the glass substrate. The metal wiring is present on one surface, and applies voltage to the light emitting element. The mark is present on one surface, and is formed of the same material as the metal wiring.

FIELD

Embodiments described herein relate generally to a light emitting panel, an optical print head, and an image forming apparatus.

BACKGROUND

In the related art, a light emitting panel in which a light emitting element such as an EL (Electro Luminescence), or the like is provided on a substrate, is used. In this light emitting panel, there is a problem in that it is difficult to understand which surface is an emitting surface of the light emitting element, and workability is not good when attaching the light emitting panel to other units, in a manufacturing process.

DETAILED DESCRIPTION

In general, according to one embodiment, a light emitting panel includes a glass substrate, a light emitting element, metal wiring, and a mark. Light passes through the glass substrate. The light emitting element is present on any one of a first plane and a second plane which is a rear surface of the first plane of the glass substrate. The metal wiring is present on one plane, and applies voltage to the light emitting element. The mark is present on one plane and is formed of the same material as that of the metal wiring.

Hereinafter, each embodiment will be described with reference to drawings.

First Embodiment

FIG. 1is a diagram which illustrates an internal configuration of an image forming apparatus100.

The image forming apparatus100includes a scanner unit1which reads an image of an original document O, and a printer unit2which forms an image on a sheet S (a member to be transferred). In the scanner unit1, a first carriage3which supports a light source9and a mirror10and a second carriage4which supports mirrors11and12, move independently of each other in a horizontal direction ofFIG. 1, and maintain the length of an optical path from the original document O to a photoelectric conversion element52so as to be constant. Light, which is emitted from the light source9and is reflected to the original document O through a document table glass53, is image-formed on the photoelectric conversion element52through the mirrors10,11and12, and a condensing lens51, after passing through the document table glass53again. The photoelectric conversion element52outputs an image signal to an optical print head13of the print unit2. In this manner, the scanner unit1sequentially reads an image of the original document O for each one line in the direction perpendicular to the plane ofFIG. 1.

In the printer unit2, a sheet S in a sheet feeding cassette21is conveyed to an image forming unit14through a sheet feeding roller22, a separating roller23, a conveying path P, and a resist roller24. The image forming unit14forms an image on the sheet S. Specifically, a photoconductive drum15of the image forming unit14rotates in a direction of an arrow D1. A charger16charges a surface of the photoconductive drum15. An optical print head6scans the photoconductive drum15in a main scanning direction (in the direction perpendicular to the plane ofFIG. 1), and forms an electrostatic latent image on the photoconductive drum15. A developing unit17develops the electrostatic latent image on the photoconductive drum15by supplying toner, and forms a toner image on the photoconductive drum15. A transfer charger18transfers the toner image to the sheet S, whereby an image is formed on the sheet S. A separating charger19separates the sheet S from the photoconductive drum15. A cleaner20removes toner remaining on the photoconductive drum15. The sheet S on which the image is formed using the image forming unit14, is conveyed to a fixer26using a conveying mechanism25. The sheet is heated and pressurized in the fixer26, and then is discharged to a discharge tray28using a discharging roller27.

FIG. 2is a cross-sectional diagram of the optical print head6. InFIG. 2, X, Y, and Z axes are orthogonal to each other.

The optical print head6extends in the depth direction with respect to the plane ofFIG. 2, emits light for one line, and exposes the photoconductive drum15for each one line. The optical print head6includes an attachment base61, a lens holder62, a SELFOC lens array63, and a light emitting panel7.

The attachment base61holds the light emitting panel7. The light emitting panel7includes a plurality of light emitting elements72in the depth direction with respect to the plane ofFIG. 2.

The lens holder62holds the SELFOC lens array63, and positions the SELFOC lens array63with respect to the light emitting panel7.

The SELFOC lens array63includes a plurality of SELFOC lenses corresponding to each light emitting element72, in the depth direction with respect to the plane ofFIG. 2. The SELFOC lens array63allows light from each light emitting element72to be image-formed on the photoconductive drum15as spot light with a necessary resolution, using each SELFOC lens.

FIG. 3is a perspective diagram of the light emitting panel7.

The light emitting panel7includes a glass substrate71, the light emitting element72, a metal wiring73, a mark74, and a sealing panel75.

The glass substrate71has an elongated shape and is formed of transparent glass which allows light to pass thorough.

The plurality of light emitting elements72is continuously provided in line in a longitudinal direction of the glass substrate71on a front surface711(a first surface) of the glass substrate71. The light emitting elements72are Organic Electro Luminescence elements. The light emitting elements72are a top emission-type, and, when a voltage is applied thereto, emit light to an upper middle side inFIG. 3, without passing through the glass substrate71. In the glass substrate71, a plane to which light is emitted is set to the front surface711, and a plane to which light is not emitted is set to a rear surface712(a second surface).

The metal wiring73is formed on the front surface711of the glass substrate71. InFIG. 3, a part of the metal wiring73is schematically shown. An appropriate material may be adopted as a material of the metal wiring73. For example, copper may be adopted as the material. A region R for connecting an external wiring is formed on one end of the glass substrate71in a longitudinal direction, on the front surface711of the glass substrate71. The metal wiring73is connected to the region R, and applies voltage to each light emitting element72.

The mark74is positioned to be separated on the other end side of the glass substrate71in a longitudinal direction, with respect to the plurality of the light emitting elements72on the front surface711of the glass substrate71. The mark74is formed of the same material as that of the metal wiring73, and is visible from the outside of the light emitting panel7. The formation of the mark74is performed at the same time and with the same material as the metal wiring73, in the process of forming the metal wiring73on the glass substrate71.

The mark74is visible from any side of the front surface711and the rear surface712of the glass substrate71. The mark74allows a worker to recognize which plane is the front surface711and which is the rear surface712of the glass substrate71, when the worker views the mark74. The mark74is, for example, formed of a character F, and is asymmetric both vertically and horizontally. As shown inFIG. 3, the mark74has a meaningful shape (a normal posture), when seen from a side where the mark74is present, in the glass substrate71, and the worker recognizes the plane711in which the mark74has the meaningful shape is the front surface711. As shown inFIG. 4, the mark74reminds the worker of the fact that the mark74has a meaningful shape, when the worker set the posture of the glass substrate71to a state inFIG. 3from the state ofFIG. 4, even when the posture of the glass substrate71inFIG. 3is changed to a posture in which both ends in a longitudinal direction are reversed, without being turned inside out. Accordingly, the mark74allows the worker to recognize that the plane711in which the mark74has a meaningful shape, is the front surface711, and to recognize whether both ends of the glass substrate71in a longitudinal direction are at a correct position.

Meanwhile, as shown inFIG. 5, when the glass substrate71is turned inside out, the mark74is not viewed as the F, and is not the meaningful shape. As long as the glass substrate71is turned inside out, as shown inFIG. 6, even when the posture of the glass substrate71inFIG. 5becomes a posture in which both ends thereof are reversed in a longitudinal direction, without being turned inside out, the mark74is not viewed as the F, and is not the meaningful shape. Accordingly, the mark74allows the worker to recognize the plane712in which the mark is not meaningful even when both ends of the glass substrate71in a longitudinal direction are reversed, as the rear surface712.

The sealing panel75(FIG. 2) is layered on the glass substrate71. The sealing panel75covers the light emitting element72, the metal wiring73, and the mark74, and seals the members72to74between the sealing panel and the glass substrate71.

In the embodiment, the worker can easily understand the plane711in which the mark74has a meaningful shape (the mark74has a normal posture) as the front surface711, since the mark74is visible from any plane711and712of the light emitting panel7(the glass substrate71), and the mark74is asymmetric vertically and horizontally. In addition, the worker can easily understand whether or not both ends of the light emitting panel7in a longitudinal direction (up and down) are positioned correctly, on the basis of the up and down direction of the mark74.

In addition, in the embodiment, since the mark74is formed of the same material as that of the metal wiring73, the mark74can be formed at the same time and with the same thickness as the metal wiring73.

As described above, in the embodiment, it is possible to allow the worker to easily recognize the direction of light emitting panel7without increasing the number of processes and cost in respect to the basic design, and without drastically changing the basic design.

Second Embodiment

FIG. 7is a perspective view of a glass substrate71A.

In the first embodiment, the light emitting element72is disposed at the center of the glass substrate71in a transverse direction (Y direction); however, in the embodiment, a light emitting element72is positioned to be biased to one side which is a lower-middle side inFIG. 7, in a transverse direction of the glass substrate71A.

In the embodiment, when the worker understands in advance that a posture of a light emitting panel7A, in which the light emitting element72is positioned downward, is a posture in which both ends of the light emitting panel7A in a longitudinal direction are at the correct position, the worker can recognize whether or not both ends of the light emitting panel7A in a longitudinal direction, are at the correct position, depending on whether the light emitting element72is on the upper side, or is on the lower side of the light emitting panel7A, in addition to a posture of the mark74.

Third Embodiment

FIG. 8is a perspective view of a glass substrate71B.

In the embodiment, a light emitting element72and a mark74are disposed on a plane712(a rear surface) in a depth side of the glass substrate713inFIG. 8. The light emitting element72is a bottom emission-type which emits light to the glass substrate71B. Accordingly, in the embodiment, the plane711in which the light emitting element72and the mark74are not present, and which is a light emitting plane, becomes a front surface711, in the glass substrate71B. In addition, in the glass substrate71B, the plane712in which the light emitting element72and the mark74are present, and light is not emitted, becomes the rear surface712.

In the embodiment, as shown inFIG. 8, the mark74has a meaningful shape when the mark74is viewed from the front surface711which is a light emitting plane with no mark74, and the plane711with no mark74can be recognized as the front surface711by the worker.

Modified Example

In each of the embodiments, the light emitting element72is an Organic Electro Luminescence element; however, the light emitting element72may be a Light Emitting Diode or an Inorganic Electro Luminescence element.

In each of the embodiments, a plurality of light emitting elements72is aligned in one line on the glass substrate71,71A or71B; however, the plurality of light emitting elements72may aligned in two or more lines on the glass substrate71,71A or71B.

The light emitting element72may be transparent or colored in a state of not being applied with voltage. The glass substrate71,71A or71B is not necessarily transparent, or may be colored, when the light emitting element72is the top emission-type.

The mark74may be positioned at an arbitrary position.

In each of the embodiments, the mark was asymmetric vertically and horizontally; however, the mark may be asymmetric in any of a vertical direction and a horizontal direction, such as T, E, or the like. Even in this case, the worker can recognize the correct direction of the light emitting panel from the relationship with the other portions of the light emitting panel, for example, the light emitting element. A case may be considered in which the worker understands in advance that the posture of the mark which is on the left side of the light emitting element72, is the correct posture of the light emitting panel7, and the mark is asymmetric in any of the vertical direction and the horizontal direction such as T or E. In this case, the worker first sets the mark of the light emitting panel to be on the left side of the light emitting element. In addition, when the mark is viewed as the meaningful shape such as T or E, it is possible to recognize that the plane being seen is the front surface which is the light emitting plane. If the mark is turned inside out, and is not seen as the meaningful shape, the plane being seen is recognized as the rear surface which is not emitting light.

The plane which is not emitting light may be set as the front surface in which the mark is seen to have the normal shape.

The member to be transferred on which images are formed using the image forming apparatus100may be an OHP (Overhead Projector), in addition to the sheet.