JP2008170724A - Scanning system lens array manufacturing method, scanning system lens array, electro-optical device, and optical apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a scanning system lens array capable of manufacturing a lens array for a scanning system capable of obtaining an excellent resolution without variation in quality, and to obtain an excellent resolution. A scanning lens array, an electro-optical device, and an optical apparatus that can be used.
A method of manufacturing a lens array for a scanning system according to the present invention includes a plurality of through openings on both surfaces of a glass substrate, and a plurality of non-penetrating grooves formed in a ring shape around each opening. A step of forming a mask having a plurality of recesses on both sides of the glass substrate, and a glass material constituting the glass substrate in each recess. A resin material filling step of filling a resin material having a high refractive index.
[Selection figure] None

Description

  The present invention relates to a method for manufacturing a lens array for a scanning system, a lens array for a scanning system, an electro-optical device, and an optical apparatus.

  In an optical apparatus such as a copying machine, a printer, or a facsimile, an image input device using a scanning system that scans an image plane with a line sensor in which light receiving elements such as CCDs are arranged on a straight line in order to obtain high-density image data. It has been known. As an optical system used in this scanning system, a rod lens array in which a plurality of rod lenses are aligned and arranged is known (for example, see Patent Document 1). The rod lens has a circular cross-sectional shape and a parabolic refractive index distribution from the center to the periphery.

  In such a rod lens array, images from adjacent lenses are overlapped to form one continuous composite image in a band shape in which the object and the image maintain the same magnification (one-to-one, magnification 1) relationship. The image is formed on a line sensor constituted by a light receiving element such as a CCD. Such a rod lens array is also used in an image output device that writes (exposes) an image pattern emitted from a light emitting array composed of LED light emitting elements or the like on a photosensitive drum, for example, in an optical printer. It is done.

  However, since such a rod lens array has a property of forming an image by superimposing images of adjacent lenses, if the position of each rod lens constituting the rod lens array is not adjusted precisely, the rod lens The optical axis and focus of the array and the line sensor or the light emitting array are not aligned. Therefore, it is necessary to design the rod lens array while finely adjusting the position of the rod lens, and there are problems that the assembly cost is high and the defect rate is high. In addition, even if the optical axis and focus between the rod lens array and the line sensor or the light emitting array are strictly adjusted, it is difficult to completely eliminate the mutual interference between the images, and a satisfactory resolution can be obtained. It was difficult. Furthermore, the end surface of each rod lens constituting the rod lens array is cut into a flat surface, and the higher the accuracy of the flat surface, the higher the resolution image can be obtained. However, the end surface of the rod lens that has been mirror-finished by cutting, polishing, or the like has a large number of minute scratches, and as a result of such scratches causing refraction and scattering at the end surfaces, there is also a problem that the resolution is lowered. .

JP-A-6-347608

  An object of the present invention is to provide a manufacturing method capable of manufacturing a lens array for a scanning system capable of obtaining an excellent resolution with a stable quality, and a scanning system capable of obtaining an excellent resolution. A lens array, an electro-optical device, and an optical apparatus are provided.

Such an object is achieved by the present invention described below.
The method for manufacturing a lens array for a scanning system according to the present invention includes a mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of a glass substrate. When,
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
The concave portion provided on one surface of the glass substrate is provided so as to correspond to the concave portion provided on the other surface.
Accordingly, it is possible to provide a manufacturing method capable of manufacturing a scanning system lens array capable of obtaining excellent resolution with stable quality.

In the manufacturing method of the lens array for a scanning system of the present invention, it is preferable that a plurality of the groove portions are provided for one opening portion provided in the mask.
Thereby, the shape of each lens provided in the lens array for a scanning system can be formed more uniformly. As a result, it is possible to manufacture a scanning system lens array with excellent quality.

In the method for manufacturing a lens array for a scanning system of the present invention, it is preferable that in the etching step, the mask is removed during the etching, and the glass substrate with the mask removed is etched again.
Thereby, a lens array for a scanning system having a lens with a large curvature radius can be easily manufactured.

In the method for manufacturing a lens array for a scanning system of the present invention, it is preferable that an average diameter of the recesses is 0.08 to 2.0 mm.
Accordingly, it is possible to more efficiently use light incident on the scanning system lens array, and it is possible to reliably prevent interference from lenses adjacent to each other and to obtain better resolution.

In the method for manufacturing a lens array for a scanning system of the present invention, it is preferable that the radius of curvature in the vicinity of the central portion of the concave portion is 0.5 to 2.0 mm.
Thereby, the spherical aberration by each lens which comprises the lens array for scanning systems is prevented more reliably, and the more excellent resolution can be obtained.
In the method for manufacturing a lens array for a scanning system of the present invention, it is preferable that an average pitch of the concave portions closest to each other is 0.7 to 8.0 mm.
Thereby, interference from lenses adjacent to each other is reliably prevented, and a higher resolution can be obtained.

In the method for manufacturing a lens array for a scanning system of the present invention, the absolute value of the difference between the refractive index of the resin material and the refractive index of the glass material constituting the glass substrate is 0.05 to 0.40. Is preferred.
As a result, interference from adjacent lenses can be reliably prevented, a higher resolution can be obtained, and the lens array for the scanning system can be downsized.

The lens array for a scanning system of the present invention is a mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of the glass substrate,
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
It is manufactured using a method for manufacturing a lens array for a scanning system in which a concave portion provided on one surface of the glass substrate and a concave portion provided on the other surface correspond to each other. And
Accordingly, it is possible to provide a scanning system lens array capable of obtaining excellent resolution.

The electro-optical device of the present invention includes a mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of the glass substrate;
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
For a scanning system manufactured by using a method for manufacturing a lens array for a scanning system provided so that a concave portion provided on one surface of the glass substrate corresponds to a concave portion provided on the other surface A lens array is provided.
Thereby, an electro-optical device with excellent resolution can be provided.

The optical device of the present invention is a mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of the glass substrate;
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
For a scanning system manufactured by using a method for manufacturing a lens array for a scanning system provided so that a concave portion provided on one surface of the glass substrate corresponds to a concave portion provided on the other surface An electro-optical device to which a lens array is applied is provided.
Thereby, an optical apparatus with excellent resolution can be provided.

Hereinafter, the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<Lens array for scanning system>
First, the lens array for a scanning system of the present invention will be described.
First, the scanning system lens array of the present embodiment will be described.
FIG. 1 is a schematic plan view of a first embodiment of a lens array for a scanning system according to the present invention as viewed from the side from which light is emitted, and FIG. 2 is an A- of the lens array for a scanning system shown in FIG. It is A sectional view.

As shown in FIGS. 1 and 2, the scanning system lens array 1 (hereinafter also simply referred to as the lens array 1) includes a plurality of first concave portions provided on the surface of the glass substrate 2 on which light is incident. 21, and a plurality of second concave portions 22 provided on the surface of the glass substrate 2 on which light is emitted, and an entrance lens 3 and an exit lens 4 filled with a resin material.
As shown in FIG. 2, the lens array 1 emits the light incident on the incident lens 3 from the light source P from the corresponding output lens 4, and the object and the image at the focal point F are 1: 1 (one-to-one, magnification 1). ). In such a lens array 1, the pair of incident lens 3 and outgoing lens 4 have functions as described above. Therefore, for example, in an image output device provided with a light emitting array in which light emitting elements are arranged in a pattern corresponding to each incident lens 3 and the lens array 1, an image pattern emitted by each light emitting element is formed on the surface of a photosensitive drum or the like. Can write.

Such a lens array 1 is formed at the same magnification as that of the image output device as described above or an image input device that forms an image pattern from a document or the like on a sensor composed of a light receiving element such as a CCD. Although it can be used as an optical system, in the following description, the case where it is used in an image output apparatus will be mainly described.
As shown in FIG. 1, in this lens array 1, a plurality of output lenses 4 are provided in a plurality of rows, and in each row, the pitch between adjacent concave portions is arranged to be constant. In the lens array 1 in which the plurality of exit lenses 4 are arranged in this way, images from the exit lenses 4 are prevented from interfering with each other, and the depth of focus is sufficiently deep.

  In addition, when the glass array 2 is viewed in plan, the lens array 1 has a center of each first concave portion 21 provided on the surface on the light incident side of the glass substrate 2 and a side from which the corresponding light is emitted. It is comprised so that the center of each 2nd recessed part 22 provided in the surface may overlap. When an image output device including such a lens array 1 and a light emitting array composed of LED light emitting elements or the like is used in an image forming apparatus such as a printer, the optical axes of the light emitting array and the lens array 1 Matching is facilitated, and the image pattern emitted from the light emitting array can be accurately written on the photosensitive drum.

  Further, in FIG. 1, the centers of the outgoing lenses 4 (each incident lens 3) on the glass substrate 2 are provided so as not to overlap each other in the vertical direction. In an image output apparatus having such a lens array 1 and a light-emitting array provided with light-emitting elements so as to correspond to the respective incident lenses 3 of the lens array 1, scanning is performed in the vertical direction in FIG. As a result, a high resolution can be obtained in proportion to the number of arrays of the exit lenses 4 (incident lenses 3) provided in the vertical direction.

  In addition, the incident lens 3 is obtained by filling the first concave portion 21 provided on the light incident side of the glass substrate 2 with a resin material having a higher refractive index than the glass material constituting the glass substrate 2. . Thereby, the light incident on the incident lens 3 can be reliably sent to the output lens 4 corresponding to the incident lens 3, and the light incident on each incident lens 3 can be prevented from interfering with each other. it can. Therefore, an image output apparatus using the lens array 1 as an optical system can obtain an accurate and high-resolution image pattern.

  In addition, the exit lens 4 is obtained by filling the second concave portion 22 provided on the light emitting side of the glass substrate 2 with a resin material having a higher refractive index than the glass material constituting the glass substrate 2. . As a result, when light is emitted from the emission lens 4, the light is emitted from the concave portion not filled with such a resin material, and the focal point is closer to the lens array 1 than the focal point where the image is formed. Can be matched. Therefore, in the image input device having the lens array 1 and a sensor composed of a light receiving element such as a CCD, the distance between the lens array 1 and the sensor can be reduced, so that the size of the device can be reduced. A more accurate image pattern can be formed on the sensor.

  Moreover, it is preferable that the average diameter when the 1st recessed part 21 is planarly viewed is 0.6-4.0 mm, it is more preferable that it is 0.8-3.0 mm, and 1.0-2. More preferably, it is 0 mm. In the lens array 1 that satisfies the above conditions, the light incident on each incident lens 3 can be used without loss, so that a more accurate image can be obtained. Moreover, such a comparatively large lens can be formed by using a method for manufacturing the lens array 1 as will be described later.

Moreover, it is preferable that the curvature radius in the center part vicinity of the 1st recessed part 21 and the 2nd recessed part 22 is 0.5-2.0 mm, It is more preferable that it is 0.6-1.5 mm, 0 More preferably, it is 8 to 1.0 mm. In the lens array 1 that satisfies the above conditions, the light incident on the incident lens 3 is more effectively prevented from interfering with each other.
Moreover, the average pitch of the first recess 21 and the second recess 22 that are closest to each other is preferably 0.7 to 8.0 mm, more preferably 1.2 to 7.0 mm. More preferably, it is 5 to 4.0 mm. Thereby, it can prevent more reliably that the light which injected into each incident lens 3 interferes with each other.

  The resin material filled in the first recess 21 and the second recess 22 is a material having a refractive index higher than that of the glass material constituting the glass substrate 2, and examples of such a resin material include various resins. The material can be used, for example, polyamide such as nylon 6, thermoplastic polyimide, liquid crystal polymer such as aromatic polyester, polyolefin such as polyphenylene oxide, polyphenylene sulfide, polyethylene, modified polyolefin, polycarbonate, acrylic (methacrylic), polymethyl Polyesters such as methacrylate, polyethylene terephthalate, polybutylene terephthalate, etc., thermoplastic resins such as polyether, polyether ether ketone, polyether imide, polyacetal, epoxy resin, phenol resin, urea resin, melamine Fat, unsaturated polyester resins, polyimide resins, thermosetting resins such as polyurethane resins, photocurable resins and the like, can be used as a mixture of two or more of them.

Among such resin materials, when a thermosetting resin or a photocurable resin is used, the following effects can be obtained. That is, the thermosetting resin is a material that hardly undergoes thermal expansion or thermal decomposition due to an external environment such as heat or light. For this reason, the 1st recessed part 21 and the 2nd recessed part 22 which were comprised with the glass material, and the resin material with which the 1st recessed part 21 and the 2nd recessed part 22 were filled are adhesiveness over a long period of time. Thus, the life of the electro-optical device (image input device, image output device, etc.) provided with such a lens array 1 can be extended.
The refractive index of the resin material filled in the first concave portion 21 and the second concave portion 22 is preferably 1.50 to 1.75, and more preferably 1.53 to 1.60. preferable. Thereby, it becomes the lens array 1 which can exhibit the above functions more reliably.

  Examples of the glass material constituting the glass substrate 2 include various glass materials such as soda glass, crystalline glass, quartz glass, lead glass, potassium glass, borosilicate glass, and alkali-free glass. It is preferable to use glass. Quartz glass has high mechanical strength and heat resistance, and has a very low coefficient of linear expansion and little change in shape due to heat. Therefore, it can be suitably used in a method for manufacturing a lens array for a scanning system as will be described later. . Further, there is an advantage that the transmittance in the short wavelength region is high and there is almost no deterioration due to light energy.

Moreover, the thickness of the glass substrate 2 is not particularly limited, but is usually preferably about 0.3 to 10 mm, and more preferably about 2 to 8 mm. The lens array 1 composed of the glass substrate 2 that satisfies the above conditions has excellent optical characteristics.
The refractive index of the glass material constituting such a glass substrate 2 is preferably 1.40 to 1.52, and more preferably 1.42 to 1.48. Thereby, it becomes the lens array 1 which can exhibit the above functions more reliably.

  The absolute value of the difference between the refractive index of the resin material filled in the first recess 21 and the second recess 22 and the refractive index of the glass material constituting the glass substrate 2 is 0.05 to 0.35. It is preferable that it is 0.10 to 0.20. Thereby, the light incident on the incident lens 3 can be sent to the corresponding exit-side exit lens 4 more efficiently, and the light incident on each entrance lens 3 can be more reliably prevented from interfering with each other. be able to. Further, the light emitted from the exit lens 4 can be imaged at a position closer to the lens array 1.

<Method for Manufacturing Lens Array for Scanning System (First Embodiment)>
Next, a first embodiment of a method for manufacturing the above-described scanning system lens array 1 will be described with reference to FIGS. 3 to 6 are process diagrams corresponding to the cross-sectional view taken along the line AA of FIG. 1, and FIG. 7 is a schematic plan view of the mask used in the present embodiment.
[Glass substrate preparation process]
First, when manufacturing the lens array 1, the glass substrate 2 is prepared.

The glass substrate 2 is preferably used with a uniform thickness and no deflection or scratches. The glass substrate 2 is preferably one whose surface is cleaned by washing or the like.
Such cleaning can be performed, for example, by etching (light etching) the surface of the glass substrate 2.
The etching method is not particularly limited, and examples thereof include wet etching and dry etching.

  When wet etching is used, the etching solution is not particularly limited, but a mixed solution of ammonium monohydrogen difluoride and sulfuric acid is preferably used. Thereby, the smoothness of the surface of the glass substrate 2 can be increased, and impurities (Na, K, etc.) on the surface of the glass substrate 2 can be suitably removed. As a result, a mask forming film can be more uniformly formed on the surface of the glass substrate 2 in a mask forming process described later. Further, the adhesion between the mask forming film and the glass substrate 2 can be improved. As a result, it is possible to prevent the masks provided on both surfaces of the glass substrate 2 from being unintentionally peeled off in an etching process described later.

[Mask formation process]
Next, a plurality of first openings 51 penetrating the surface of the glass substrate 2 on which light is incident as described above, and a plurality of penetrations formed in a ring shape with the first opening 51 as a center. A first mask 5 having a first groove portion 52 that is not formed is formed. Along with this, a plurality of penetrating second openings 61 and a plurality of penetrating rings formed around the second opening 61 are formed on the surface of the glass substrate 2 on which light is emitted. A first mask 6 having no second groove 62 is formed.

Hereinafter, this process will be described in detail with reference to the accompanying drawings.
(Mask forming film forming process)
First, as shown in FIG. 3A, a first mask forming film 50 and a second mask are respectively formed on the surface on which light is incident and the surface on which light is emitted of the prepared glass substrate 2. A forming film 60 is formed (mask forming film forming step).

  First mask formation film 50 and second mask formation film 60 (hereinafter, the first mask formation film 50 and the second mask formation film 60 are also collectively referred to as a mask formation film). Is capable of forming openings and grooves as described later by physical method or laser light irradiation in the opening forming process and groove forming process described later, and has resistance to etching in the etching process described later Is preferred. In other words, the mask forming film is preferably configured so that the etching rate is substantially equal to that of the glass substrate 2 or smaller than that of the glass substrate 2. As a method for forming such a film for forming a mask, the glass substrate 2 may be formed on one side or on both sides at the same time.

From this point of view, the material forming the mask forming film is, for example, a metal such as Cr, Au, Ni, Ti, Pt, an alloy containing two or more selected from these, an oxide of the metal (metal Oxide), silicon, resin and the like. Further, the mask forming film may have a laminated structure of a plurality of layers made of different materials such as Cr / Au.
The method for forming the mask forming film is not particularly limited, but when the mask forming film is made of a metal material (including an alloy) such as Cr or Au or a metal oxide (for example, Cr oxide), the mask forming film is For example, it can be suitably formed by vapor deposition or sputtering. When the mask forming film is made of silicon, the mask forming film can be suitably formed by, for example, a sputtering method or a CVD method.

  When the mask forming film is mainly composed of Cr oxide or Cr, the first opening 51 and the second opening 61 can be easily formed in the opening forming step described later, and the groove Also in the forming step, the first groove portion 52 and the second groove portion 62 can be easily formed. Moreover, the glass substrate 2 can be more reliably protected in the etching process described later. Further, when the mask forming film is mainly composed of Cr, for example, an ammonium monohydrogen difluoride solution can be used as an etching solution in an opening forming step described later. Since ammonium monohydrogen difluoride is not a poisonous deleterious substance at a concentration of 4 wt% or less, it is possible to more reliably prevent the human body and the environment from being affected.

  When the mask forming film is a laminate having a layer mainly composed of chromium and a layer mainly composed of chromium oxide, the average thickness of the chromium layer is X [nm], When the average thickness of the layer is Y [nm], it is preferable that the relationship of 0.01 ≦ Y / X ≦ 0.8 is satisfied, and the relationship of 0.1 ≦ Y / X ≦ 0.5 is satisfied. Is more preferable. By satisfying such a relationship, an opening having a desired size, which will be described later, can be formed with higher accuracy.

  The thickness of the film for forming a mask (the first mask 5 and the second mask 6) varies depending on the material constituting the mask forming film, but is preferably 5 to 500 nm, and preferably 40 to 150 nm. Is more preferable. Thereby, formation of an opening and a groove as described later is facilitated while maintaining resistance to etching, and the size of the opening and the groove as described later can be more easily controlled. If the thickness is less than the lower limit value, the shape of the opening formed in the opening forming step described later may be distorted depending on the constituent material of the mask forming film. Moreover, in the groove part formation process described later, depending on the method of forming the groove part, the groove part may penetrate to the glass substrate, and it may be difficult to form the groove part as described later. Further, when wet etching is performed in an etching process described later, the masked portion of the glass substrate 2 may not be sufficiently protected. On the other hand, when the upper limit value is exceeded, depending on the constituent material of the mask forming film, it becomes difficult to form a through opening in an opening forming step described later. Further, the mask forming film may be easily peeled off due to the internal stress of the mask forming film.

(Opening formation process)
Next, a plurality of first openings 51 and second openings 61 are respectively formed in the first mask forming film 50 and the second mask forming film 60 (opening forming step). The first opening 51 and the second opening 61 are through holes that penetrate to the glass substrate 2.
The first opening 51 and the second opening 61 may be formed by any method, but are preferably formed by a physical method or laser light irradiation. Thereby, for example, the lens array 1 can be manufactured with high productivity. In particular, the first recess 21 and the second recess 22 can be easily formed on a large-area substrate.

  Examples of the physical method for forming the first opening 51 and the second opening 61 include blasting such as shot blasting and sand blasting, press, dot printer, tapping, rubbing, and the like. When the first opening 51 and the second opening 61 are formed by blasting, the first opening 51 and the second opening can be efficiently performed in a shorter time even with the glass substrate 2 having a relatively large area. 61 can be formed.

In addition, when the first opening 51 and the second opening 61 are formed by laser light irradiation, the type of laser light to be used is not particularly limited, but is ruby laser, semiconductor laser, YAG laser, femtosecond. Examples thereof include a laser, a glass laser, a YVO ₄ laser, a Ne—He laser, an Ar laser, and a CO ₂ laser excimer laser. Moreover, you may use wavelengths, such as SHG of each laser, THG, and FHG. When the first opening 51 and the second opening 61 are formed by laser light irradiation, the size of the first opening 51 and the second opening 61 to be formed and the adjacent first opening It is possible to easily and accurately control the spacing between the 51 and the spacing between the adjacent second openings 61.

  Further, the shape and size of the opening formed in this step is not particularly limited, but it is substantially circular and the diameter is preferably 10 μm or less, more preferably 1 to 8 μm, and 3 to 3 More preferably, it is 6 μm. When the diameter of the opening is a value within the above range, a concave portion having a desired shape can be reliably formed on the surface of the glass substrate 2 in the first etching step described later.

In the following description, a plurality of first openings 51 and second openings 61 are formed in the first mask forming film 50 and the second mask forming film 60, respectively, by laser light irradiation. The case will be described.
First, as shown in FIG. 3B, a second opening 61 is formed in the second mask forming film 60 provided on the glass substrate 2.

When the second opening 61 is formed in the second mask formation film 60 by laser light irradiation, the second mask formation film 60 of the glass substrate 2 is formed as shown in FIG. By irradiating the surface of the second mask forming film 60 with the laser beam 41 from the laser 40 arranged perpendicularly to the surface opposite to the surface, the second mask forming film A second opening 61 is formed at 60. While moving the laser 40 as indicated by arrows A1 and A2 in the figure, the laser beam 41 is intermittently irradiated over the entire surface of the second mask forming film 60, and a plurality of second openings 61 are formed. The second mask formation film 60 is formed over the entire surface.
Next, as shown in FIG. 3C, the mask forming film 50 provided on the glass substrate 2 is provided on the second mask forming film 60 on the other surface side of the glass substrate 2. The first opening 51 is similarly formed at a location corresponding to the second opening 61. Thus, a mask forming film having an opening as shown in FIG.

(Groove formation process)
Next, the first mask formation film 50 and the second mask formation film 60 provided with the openings as shown in FIG. 4A are respectively centered on the first openings 51. The ring-shaped first groove 52 and the ring-shaped second groove 62 centering on each second opening 61 are formed to obtain the first mask 5 and the second mask 6 (groove Forming step). Note that neither the first groove portion 52 nor the second groove portion 62 penetrates to the glass substrate 2.

  As described above, the first mask 5 and the second mask 6 are respectively provided with the first opening 51 and the second opening 62 penetrating to the glass substrate 2 and the rings provided around the respective openings. A first groove portion 52 and a second groove portion 62 are formed. For this reason, when the glass substrate 2 is etched using the first mask 5 and the second mask 6 in the etching process described later, a plurality of the masks provided in the first mask 5 and the second mask 6 are used. The glass substrate 2 is etched from the opening. Thereafter, the glass substrate 2 is isotropically etched from each opening, and the edge of each recess that is being formed is formed in each ring-shaped groove provided in the first mask 5 and the second mask 6. When the vicinity of the corresponding position is reached, the mask surrounded by each ring-shaped groove is peeled off. By using the first mask 5 and the second mask 6 as described above, when further etching is performed thereafter, the etching solution can be sufficiently distributed in the recess that is being formed. As a result, it is possible to suppress variations in the etching rate between the recesses that are being formed, and to sufficiently reduce the variation in shape between the recesses provided on both surfaces of the glass substrate 2 that is finally obtained. can do.

  On the other hand, when etching is performed using a mask having no groove as described above, the size of the opening is so small that it does not sufficiently reach the recess where the etching solution is being formed. For this reason, it becomes difficult to suppress variation in shape between the recesses. As a result, it becomes difficult to make the positions of the focal points formed by each pair of the incident lens 3 and the outgoing lens 4 provided in the finally obtained lens array 1 uniform, and the obtained image is obtained. The depth of focus will be shallow.

In addition, the width between the outer periphery and the inner periphery of each ring-shaped groove provided in the first mask 5 and the second mask 6 is equal to each opening provided in the first mask 5 and the second mask 6. It is preferable that the diameter is smaller than the diameter. Thereby, in the etching process to be described later, the glass substrate 2 is etched, and the edges of the recesses that are being formed become ring-shaped grooves provided in the first mask 5 and the second mask 6. When the vicinity of the corresponding position is reached, the mask in the region surrounded by each groove can be more reliably peeled off.
Further, the radius of each ring-shaped groove provided in each mask forming film is preferably 5 to 400 μm, and more preferably 50 to 100 μm. Thereby, in the etching process mentioned later, when forming a comparatively large recessed part in the glass substrate 2, each recessed part can be formed uniformly.

Further, the ring-shaped grooves provided in the first mask 5 and the second mask 6 are preferably 50 to 95% deep, and 60 to 80% deep, of the thickness of each mask. It is more preferable that Thereby, in the etching process to be described later, when the edge of each recess that is being formed reaches a position corresponding to each of the ring-shaped grooves provided in the first mask 5 and the second mask 6. The mask in the region surrounded by each groove can be peeled off more reliably. Further, when the glass substrate 2 is etched, it is possible to more reliably prevent the etching liquid from entering the glass substrate 2 from each groove portion.
The first groove 52 and the second groove 62 are preferably formed by laser light irradiation, and the first opening 51 and the second opening 61 are formed as the types of laser light to be used. By using the laser used at the time, each groove portion can be formed.

In the following description, a case where a plurality of first groove portions 52 and second groove portions 62 are formed in the first mask forming film 50 and the second mask forming film 60, respectively, by laser light irradiation will be described. To do.
First, as shown in FIG. 4B, a ring-shaped groove 62 centering on the second opening 61 provided in the second mask forming film 60 provided on the glass substrate 2 is formed. .

When the ring-shaped groove 62 is formed in the second mask forming film 60 by laser light irradiation, the second mask forming film 60 of the glass substrate 2 is formed as shown in FIG. Laser light 41 is irradiated toward the surface of the second mask forming film 60 from the laser 40 arranged perpendicularly to the surface on the side facing the surface so that a ring shape with a predetermined diameter is obtained. A second ring-shaped groove 62 is formed in the second mask forming film 60 while moving the laser 40.
In this way, the second mask forming film 60 is irradiated with the laser beam 41, and the second groove 62 is formed in the second mask forming film 60 as shown in FIG. The mask 6 is obtained.

  Next, as shown in FIG. 4C, the mask forming film 50 provided on the glass substrate 2 is provided on the second mask forming film 60 on the other surface side of the glass substrate 2. A first groove 52 is similarly formed at a location corresponding to the second opening 61 to obtain the first mask 5. FIG. 7 shows a schematic plan view when the second mask 6 is viewed in plan among the masks thus obtained.

[Etching process]
Next, the glass substrate 2 is etched to form a first recess 21 on the surface of the glass substrate 2 on which light is incident. Along with this, a second recess 22 is formed on the surface of the glass substrate 2 on which light is emitted.
Hereinafter, this process will be described in detail with reference to the accompanying drawings.
(First etching process)
First, the glass substrate 2 covered with the first mask 5 and the second mask 6 is etched.

  The etching method is not particularly limited, and examples thereof include wet etching and dry etching. It is preferable to use a wet etching method. Thereby, the 1st recessed part 21 and the 2nd recessed part 22 can be formed suitably. If, for example, an etchant (hydrofluoric acid-based etchant) containing hydrofluoric acid (hydrogen fluoride) is used as the etchant, the glass substrate 2 can be etched more selectively, and the first recess 21 can be etched. And the 2nd recessed part 22 can be formed suitably.

In the following description, a case where wet etching is used will be described.
As shown in FIG. 5B, etching (wet etching) is performed on the glass substrate 2 covered with the first mask 5 and the second mask 6 as shown in FIG. The glass substrate 2 is etched from a portion where the first mask forming film 50 and the second mask forming film 60 are not formed, that is, from the plurality of first openings 51 and the second openings 61. Etching isotropically from each opening.

After that, as shown in FIG. 5C, the edge of the recess that is being formed has reached a position corresponding to each of the ring-shaped grooves provided in the first mask 5 and the second mask 6. At this time, the mask in the region surrounded by each groove is peeled off. Thereby, when etching is further performed on the glass substrate, the etching solution can be sufficiently distributed in each of the recesses that are being formed. As a result, the variation in etching rate between the recesses being formed can be made sufficiently small, and the variation in the shape between the recesses finally formed can be made sufficiently small. it can.
As shown in FIG. 5D, after the mask in the region surrounded by each groove portion is peeled off, further etching is performed, and the first recess 21 and the second recess that are finally formed on both surfaces of the glass substrate 2. Etching is temporarily terminated in a state where a recess having a diameter smaller than that of the recess 22 is formed.

(Mask removal process)
Next, as shown in FIG. 6E, the first mask 5 and the second mask 6 are removed.
The first mask 5 and the second mask 6 can be removed by, for example, etching.
(Second etching process)
Next, the glass substrate from which the first mask 5 and the second mask 6 have been removed is etched again to form a plurality of first recesses 21 on the surface of the glass substrate 2 on which light is incident. To do. At the same time, a plurality of second recesses 22 are formed on the surface of the glass substrate 2 where light is emitted. Note that the sizes of the first concave portion 21 and the second concave portion 22 finally formed are sizes corresponding to the sizes of the incident lens 3 and the outgoing lens 4 described above, respectively.

As the etching method, the method described in the first etching step can be used.
In this step, a case where wet etching is used will be described as in the first etching step.
Etching is performed again on the glass substrate 2 from which the mask as shown in FIG. 6E has been removed, and as shown in FIG. 6F, a plurality of first recesses 21 and a plurality of recesses are formed in the glass substrate 2. The second recess 22 is formed. Thus, by etching the glass substrate 2 with the mask removed, the radius of curvature of the first recess 21 and the second recess 22 that are finally formed can be made larger. Thereby, the spherical aberration of the lens array 1 can be more reliably suppressed, and the obtained depth of focus is sufficiently deep. Also, by changing the etching conditions (time, etching solution used, etc.) in the first etching step and the second etching step, the radius of curvature near the central portion of the recess and the peripheral portion can be easily controlled. Therefore, the lens array 1 having an arbitrary performance can be manufactured.

[Resin material filling process]
Next, as shown in FIG. 6 (G), the first concave portion 21 and the second concave portion 22 provided in the glass substrate 2 are filled with the resin material as described above to obtain the lens array 1. In addition, the material with which the 1st recessed part 21 and the 2nd recessed part 22 are filled may be the same material, and may differ.

  The method for filling the resin material is not particularly limited. For example, when the material filled in the first recess 21 and the second recess 22 is a thermoplastic resin, the glass of the resin material to be filled is used. The film made of the resin material is pressed against both surfaces of the glass substrate 2 while applying heat so that the temperature is not lower than the transition temperature and does not thermally decompose, and the first recess 21 and the second recess 22 Is filled with a resin material. Thereafter, cooling is performed, and excess resin is removed by cutting or the like so that the outer surfaces of the entrance lens 3 and the exit lens 4 are the same height as the surface of the glass substrate 2. The lens array 1 provided with the lens 3 and the exit lens 4 can be obtained. Further, after removing the excess resin by cutting or the like, the lens array 1 is subjected to heat treatment at a temperature equal to or higher than the glass transition temperature of the filled resin material, so that the outer surfaces of the entrance lens 3 and the exit lens 4 are made. It becomes smoother and unintentional scattering and refraction at the outer surfaces of the entrance lens 3 and the exit lens 4 can be suppressed.

  Moreover, when the resin material with which the 1st recessed part 21 and the 2nd recessed part 22 are filled is a photocurable resin, 2P method can be used. The outer surfaces of the entrance lens 3 and the exit lens 4 obtained by using the 2P method are smooth without unevenness. Thereby, when light is incident on each incident lens 3 or light is emitted from each output lens 4, unintentional scattering and refraction at the outer surfaces of each incident lens 3 and the output lens 4 occur. Such a lens array 1 can be suitably used for an electro-optical device that requires high resolution and deep focal depth.

  In the above description, each opening and each groove are formed by irradiating each mask with laser light. However, the manufacturing method of the present embodiment is not limited to this, and for example, each groove As a method for forming the film, there is a method in which a resist is applied to a glass substrate, a ring-shaped groove is patterned by photoetching, and a mask forming film is processed to a predetermined depth by dry etching. The opening can also be formed by a similar method. By using this method, the depth of the groove can be accurately adjusted.

  In the above description, the mask 6 provided on both surfaces of the glass substrate 2 has been described as being removed, but a part of the mask 6 may be left without being completely removed. For example, when the first concave portion and the second concave portion are viewed from the outer surface side, a part of the mask is removed with a laser or the like so that the first concave portion and the second concave portion are completely exposed, and the glass substrate is not formed with each concave portion. A lens array with a mask remaining may be used. In such a lens array, depending on the material of the mask, the mask that has not been removed has the effect of a shielding film, and can more effectively prevent light incident from each incident lens from interfering with each other. .

<Method for Manufacturing Lens Array for Scanning System (Second Embodiment)>
Next, a second embodiment of the method for manufacturing the above-described scanning system lens array 1 will be described with reference to FIGS. In the following description, differences from the above-described embodiment (first embodiment) will be mainly described, and description of similar matters will be omitted. 8 and 9 are process diagrams corresponding to the cross-sectional view taken along the line AA of FIG. 1, and FIG. 10 is a schematic plan view of the mask used in this embodiment.

In the present embodiment, as a mask for covering the glass substrate 2, a mask in which a plurality of ring-shaped grooves provided around the openings provided in the respective masks are provided for one opening is used. This is different from the first embodiment described above.
In the following description, the description will focus on the etching process of this embodiment in which the glass substrate 2 is etched using the mask provided with the opening and the groove as described above.

  As shown in FIG. 8 (A), the first mask 5 ′ includes a plurality of first openings 51 ′ penetrating through and a first opening 51 ′. Two non-penetrating first groove portions formed in a ring shape around 51 ′ are provided. At the same time, the second mask 6 ′ has a plurality of penetrating second openings 61 ′ and one second opening 61 ′ in a ring shape centering on each second opening 61 ′. Two non-penetrating second groove portions are formed. FIG. 10 shows a schematic plan view of the second mask 6 ′ among the masks having such a configuration when viewed in plan.

  By performing etching (wet etching) on the glass substrate 2 covered with the first mask 5 ′ and the second mask 6 ′ as described above, as shown in FIG. 8B, the glass substrate 2 Is etched from a portion where the first mask forming film 50 and the second mask forming film 60 are not formed, that is, from the plurality of first openings 51 ′ and second openings 61 ′.

  Thereafter, as shown in FIG. 8C, the glass substrate 2 is isotropically etched from each opening, and the edge of each recess that is being formed has each ring-shaped groove provided in each mask. Of each of the first groove portions 52 ′ and the second groove portions when reaching the vicinity of the position corresponding to each of the first groove portions 52 ′ and the second groove portions 62 ′ provided on the side close to the opening. The mask in the region surrounded by 62 'is peeled off. After that, as shown in FIG. 9D, the etching further proceeds, and the edge of each recess that is being formed becomes the first groove 53 ′ and the second groove 63 ′ remaining in each mask. When the vicinity of the corresponding position is reached, the mask remaining in the region surrounded by the first groove portions 53 ′ and the second groove portions 63 ′ is peeled off. Thereafter, similarly to the first embodiment described above, the mask removing step and the second etching step are performed, and the first concave portion 21 and the second concave portion 22 are formed on the surface of the glass substrate 2. By etching the glass substrate 2 using such a mask, the diameter of the opening provided in the mask increases stepwise as the diameter of each recess that is being formed increases. Become. Thereby, the etching solution can be sufficiently distributed in each recess that is being formed, so that the variation in shape between the recesses provided in the finally obtained glass substrate 2 is made smaller. Can do. In addition, a recess having a relatively large diameter can be efficiently and accurately manufactured.

  In the above description, two grooves are formed for each opening. However, the mask used in the present embodiment is not limited to this, and three or more for each opening. The groove portion may be formed. Even when the glass substrate is etched through the mask provided with such openings and grooves, the above-described effects can be obtained.

<Electro-optical device and optical equipment>
Next, the electro-optical device (image output device) of the present invention including the above-described scanning system lens array and the optical apparatus (image forming device) of the present invention are based on the embodiments shown in FIGS. This will be described in detail.
FIG. 11 is a schematic diagram showing a configuration of an image forming apparatus to which an image output apparatus including a scanning system lens array of the present invention is applied, and FIG. 12 shows an image output apparatus to which the scanning system lens array 1 of the present invention is applied. It is a conceptual diagram.

  As shown in FIG. 11, the image forming apparatus 100 includes a toner storage unit 101 that stores toner, a cylindrical photosensitive member 102 that develops a toner image, a developing roller 103 that supplies toner to the photosensitive member 102, and a toner A supply roller 104 that supplies toner from the storage unit 101 to the developing roller 103, an intermediate transfer roller 105 and a secondary transfer roller 106 that transfer the toner image developed by the photosensitive member 102 to the recording medium, and the toner image transferred to the recording medium And a fixing unit 107 that fixes the toner image on the recording medium.

Around the photosensitive member 102, a charger 108 that uniformly charges the outer peripheral surface of the photosensitive member 102, and the outer peripheral surface that is uniformly charged by the charger 108 are sequentially synchronized with the rotation of the photosensitive member 102. An image output device (line head) 109 provided with the above-described scanning system lens array 1 for line scanning is provided.
In such a configuration, after the surface of the photosensitive member 102 is uniformly charged by the charger 108, exposure according to information to be recorded is performed by an image output device 109 described later. As a result, an electrostatic latent image is formed on the surface of the photoreceptor 102.

Here, the image output device 109 will be described with reference to the drawings.
As shown in FIG. 11, the image output device 109 includes the lens array 1 as described above and a light emitting element array 70 provided on the light incident surface side of the lens array 1.
The light emitting element array 70 has a plurality of light emitting elements 71.
The light emitting elements 71 are arranged in the same pattern as the plurality of incident lenses 3 (outgoing lenses 4) of the lens array 1 described above.

That is, the light emitting element array 70 and the lens array 1 are configured such that the light emitting element 71 and the incident lens 3 (outgoing lens 4) correspond to 1: 1.
In addition, the light emitting element array 70 and the lens array 1 are configured such that the light beams emitted from the respective light emitting elements 71 pass through the corresponding pair of incident lenses 3 and outgoing lenses 4 to the photoconductor 102. They are integrated by an unillustrated integration means (casing or the like) so as to form an image. The optical axes of each pair of the incident lens 3 and the outgoing lens 4 pass through the center of the corresponding light emitting element 71.

  A one-dimensional image expressed by the combination of the light emitting elements 71 that are lit is formed on the photosensitive member 102 via the lens array 1. Then, with the rotation of the photosensitive member 102 (rotation in the direction perpendicular to the paper surface in FIG. 11), such optical image transmission is repeated, and a two-dimensional image (electrostatic latent image) is transmitted onto the photosensitive member 102 (exposure). ) In addition, the site | part exposed by the light condensed with each lens provided in the lens array 1 for scanning systems corresponds to 1 pixel.

Incidentally, a rod lens array has been conventionally used for an image output device (optical system) of such an image forming apparatus. However, since the rod lens array is an optical system that forms an image by superimposing the images of the adjacent rod lenses, it is difficult to reduce the focal point, and as a result, it is difficult to obtain a sufficient resolution.
On the other hand, by applying the scanning system lens array 1 of the present invention to the optical system of the image forming apparatus, the size of one pixel can be made sufficiently small, so that the resolution is higher. And the depth of focus can be sufficiently deep.

The supply roller 104 rotates to face the developing roller 103 and has a function of supplying toner to the developing roller 103.
The developing roller 103 has a function of rotating at the same speed as the photosensitive member 102 and transferring the toner to the electrostatic latent image. As described above, the toner is transferred to the electrostatic latent image on the photoconductor 102, whereby a toner image is formed on the photoconductor 102.

After the toner image formed on the photoconductor 102 is transferred to the intermediate transfer roller 105, a transfer current is passed through the secondary transfer roller 106, and the toner is applied to a recording medium such as paper passing between the two. The image is transferred.
The fixing unit 105 includes a pressure roller 1071 and a heating roller 1072, and has a function of fixing the toner image transferred to the recording medium to the recording medium by pressing and heating.

Since the image forming apparatus 100 includes the scanning system lens array 1 as described above, it can form an image with high resolution and stable quality. In addition, when mass-produced, quality variations among manufactured image forming apparatuses can be made sufficiently small.
In addition to the image forming apparatus (printer) of FIG. 11, examples of the optical apparatus of the present invention include a facsimile and a scanner. Needless to say, the above-described lens array for a scanning system of the present invention can be applied as an electro-optical device of these various optical devices.

The scanning system lens array and the manufacturing method thereof, the electro-optical device, and the optical apparatus of the present invention have been described based on the illustrated embodiments, but the present invention is not limited to these.
For example, in the method for manufacturing a lens array for a scanning system according to the present invention, an arbitrary process can be added as necessary.

In the above description, the groove is formed after the opening is formed. However, a method of forming the opening after forming the groove may be used.
In the above description, the structure in which the laser beam is irradiated while moving the laser in a one-dimensional manner in the opening forming step has been described. However, the laser beam irradiation can be performed two-dimensionally or three-dimensionally. It may be performed while being moved.

(Example 1)
A lens array for a scanning system was manufactured as follows.
First, a 0.15 μm thick oxide film is formed by sputtering on both surfaces of a glass substrate (thickness: 4.8 mm, refractive index: 1.46) made of quartz glass and having a length in the longitudinal direction of 250 mm. A Cr film / Cr / Cr oxide film (mask forming film) was formed.

Next, laser processing was performed on the mask forming films to form a large number of openings in each mask forming film.
The laser processing was performed using a YAG laser under the conditions of an energy intensity of 2 mW, a beam diameter of 5 μm, and an irradiation time of 0.1 ms.
Thereby, a plurality of openings were formed in each mask forming film. The average diameter of the openings was 4 μm, and the formation density of the openings was 2000 / cm ² .

Further, laser processing was performed on each mask forming film, and one ring-shaped groove portion was formed for each opening, with each opening as a center.
The average radius of each groove formed in this way was 300 μm.
Laser processing was performed using a YAG laser under the conditions of energy intensity 1 mW, beam diameter 2 μm, and irradiation time 0.05 ms.

The average distance between the widths of the grooves thus obtained was 2 μm.
As a result, a groove corresponding to each opening was formed in each mask forming film. In this way, a mask having openings and grooves on both surfaces of the glass substrate was formed.
Next, wet etching is performed on the glass substrate, and a plurality of first recesses and a plurality of second recesses are respectively formed on the surface on the light incident side of the glass substrate and the surface on the light emitting side. It formed by the method like.

First, the glass substrate was immersed for 5 hours using 4 wt% aqueous solution of ammonium hydrogen difluoride (room temperature) as an etchant. It was confirmed that the mask surrounded by the groove was peeled off in the etching solution after 4 hours from the start of immersion.
Next, the glass substrate was taken out from the above etching solution and immersed in a mixed aqueous solution of ceric ammonium nitrate and perchloric acid for 30 minutes to remove the Cr oxide film / Cr / Cr oxide film (mask).

After removing the mask, the glass substrate was further immersed in an etching solution having the same configuration as described above for 7 hours to form a first recess and a second recess in the glass substrate.
Each glass substrate having a plurality of recesses on both sides manufactured as described above is filled with liquid polymethyl methacrylate (PMMA) (refractive index: 1.60), irradiated with ultraviolet rays, and cured. By doing so, a lens array for a scanning system was produced.
The diameter of each first recess and each second recess formed in this manner was 2.0 mm. Moreover, the depth of each 1st recessed part and each 2nd recessed part was 1.0 mm (= curvature radius). Moreover, the average pitch of each 1st recessed part and each 2nd recessed part which adjoined most was 3.5 mm.

(Example 2)
First, a 0.15 μm thick oxide film is formed by sputtering on both surfaces of a glass substrate (thickness: 4.8 mm, refractive index: 1.46) made of quartz glass and having a length in the longitudinal direction of 250 mm. A Cr film / Cr / Cr oxide film (mask forming film) was formed.
Next, laser processing was performed on the mask forming films to form a large number of openings in each mask forming film.

The laser processing was performed using a YAG laser under the conditions of an energy intensity of 2 mW, a beam diameter of 5 μm, and an irradiation time of 0.1 ms.
Thereby, a plurality of openings were formed in each mask forming film. The average diameter of the openings was 4 μm, and the formation density of the openings was 2000 / cm ² .
Further, laser processing was performed on each mask forming film to form two ring-shaped grooves with respect to each opening.

The average radius of the groove portion provided on the opening side of each groove portion thus formed is 200 μm, and the average radius of the groove portion provided on the outer side of the groove portion provided on the opening side of each groove portion. Was 400 μm.
Laser processing was performed using a YAG laser under the conditions of energy intensity 1 mW, beam diameter 2 μm, and irradiation time 0.05 ms.

The average distance between the widths of the grooves thus obtained was 2 μm.
As a result, a groove corresponding to each opening was formed in each mask forming film. In this way, a mask having openings and grooves on both surfaces of the glass substrate was formed.
Next, wet etching is performed on the glass substrate, and a plurality of first recesses and a plurality of second recesses are respectively formed on the surface on the light incident side of the glass substrate and the surface on the light emitting side. It formed by the method like.

  First, the glass substrate was immersed for 5 hours using 4 wt% aqueous solution of ammonium hydrogen difluoride (room temperature) as an etchant. In addition, 3 hours after starting to immerse, it was confirmed that the mask surrounded by the groove near the opening was peeled off in the etching solution. Similarly, after 4 hours, it was confirmed that the mask surrounded by the groove on the side away from the opening was completely removed in the etching solution.

Next, the glass substrate was taken out from the above etching solution and immersed in a mixed aqueous solution of ceric ammonium nitrate and perchloric acid for 30 minutes to remove the Cr oxide film / Cr / Cr oxide film (mask).
After removing the mask, the glass substrate was further immersed for 3 hours in an etching solution having the same structure as described above to form a first recess and a second recess in the glass substrate.

Scanning is carried out by filling a liquid epoxy resin (refractive index: 1.59) into each concave portion of a glass substrate having a plurality of concave portions on both sides manufactured as described above, and irradiating with ultraviolet rays and curing. A lens array for the system was produced.
The diameter of each first recess and each second recess thus formed was 1.0 mm. Moreover, the depth of each 1st recessed part and each 2nd recessed part was 0.8 mm (= curvature radius). Moreover, the average pitch of each 1st recessed part and each 2nd recessed part which adjoined most was 2.5 mm.

(Evaluation)
In each of the embodiments, a high-resolution lens array for a scanning system having a deeper focal depth than that of a conventional rod lens array could be manufactured without variation in quality.
In each embodiment, the focal depth is deeper than that of the conventional rod lens array, and the focal position is at a position closer to each scanning system lens array.

  Further, an image forming apparatus having a structure as shown in FIG. 11 was manufactured using the scanning system lens array obtained in each example. When an image was printed using the obtained image forming apparatus, the image forming apparatus provided with the scanning system lens array of each example was compared with the conventional image forming apparatus provided with the rod lens array. An image with a high depth and high resolution was obtained.

It is the typical top view which looked at the lens array for scanning systems of the present invention from the side from which light was emitted. It is the sectional view on the AA line in FIG. 1 of the lens array for scanning systems of this invention. It is a typical process figure showing a 1st embodiment of a manufacturing method of a lens array for scanning systems. It is a typical process figure showing a 1st embodiment of a manufacturing method of a lens array for scanning systems. It is a typical process figure showing a 1st embodiment of a manufacturing method of a lens array for scanning systems. It is a typical process figure showing a 1st embodiment of a manufacturing method of a lens array for scanning systems. It is a typical top view which shows the 2nd mask used in 1st Embodiment of the manufacturing method of the lens array for scanning systems. It is a typical process figure showing a 2nd embodiment of a manufacturing method of a lens array for scanning systems. It is a typical process figure showing a 2nd embodiment of a manufacturing method of a lens array for scanning systems. It is a typical top view which shows the 2nd mask used in 2nd Embodiment of the manufacturing method of the lens array for scanning systems. It is a schematic diagram which shows the structure of the optical instrument (image forming apparatus) of this invention. 1 is a conceptual diagram of an electro-optical device (image output device) of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Scanning system lens array 2 ... Glass substrate 21 ... 1st recessed part 22 ... 2nd recessed part 3 ... Incident lens 4 ... Outgoing lens 5 (5 ') ... 1st mask 50 ... 1st mask formation film 51 (51 ') ... 1st opening 52 (52', 53 ') ... 1st groove part 6 (6') ... 2nd mask 60 ... 2nd mask formation film 61 (61 ') ... 1st 2 opening 62 (62 ', 63') ... 2nd groove part 40 ... Laser 41 ... Laser light 70 ... Light emitting element array 71 ... Light emitting element 100 ... Image forming apparatus 101 ... Toner accommodating part 102 ... Photoconductor 103 ... Development Roller 104 ... Supply roller 105 ... Intermediate transfer roller 106 ... Secondary transfer roller 107 ... Fixing unit 1071 ... Pressure roller 1072 ... Heating roller 108 ... Charger 109 ... Image output device (line) P) P ... Light source F ... Focus

Claims (10)

A mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of the glass substrate;
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
A method of manufacturing a lens array for a scanning system, wherein a concave portion provided on one surface of the glass substrate and a concave portion provided on the other surface correspond to each other.   The method for manufacturing a lens array for a scanning system according to claim 1, wherein a plurality of the groove portions are provided for one opening portion provided in the mask.   3. The method for manufacturing a lens array for a scanning system according to claim 1, wherein in the etching step, the mask is removed during the etching, and the glass substrate in a state where the mask is removed is etched again.   The method for manufacturing a lens array for a scanning system according to any one of claims 1 to 3, wherein an average diameter of the recesses is 0.08 to 2.0 mm.   The method of manufacturing a lens array for a scanning system according to any one of claims 1 to 4, wherein a radius of curvature in the vicinity of a central portion of the concave portion is 0.5 to 2.0 mm.   The method for manufacturing a lens array for a scanning system according to any one of claims 1 to 5, wherein an average pitch of the concave portions closest to each other is 0.7 to 8.0 mm.   The scanning system according to any one of claims 1 to 6, wherein an absolute value of a difference between a refractive index of the resin material and a refractive index of a glass material constituting the glass substrate is 0.05 to 0.40. A method of manufacturing a lens array. A mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of the glass substrate;
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
It is manufactured using a method for manufacturing a lens array for a scanning system in which a concave portion provided on one surface of the glass substrate and a concave portion provided on the other surface correspond to each other. Lens array for scanning system. A mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of the glass substrate;
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
For a scanning system manufactured by using a method for manufacturing a lens array for a scanning system provided so that a concave portion provided on one surface of the glass substrate corresponds to a concave portion provided on the other surface An electro-optical device comprising a lens array. A mask forming step of forming a mask having a plurality of openings and a plurality of grooves formed in a ring shape around the openings on both surfaces of the glass substrate;
Etching the glass substrate through the opening, an etching step of forming a plurality of recesses on both sides of the glass substrate;
A resin material filling step of filling the recess with a resin material having a refractive index higher than that of the glass material constituting the glass substrate;
For a scanning system manufactured by using a method for manufacturing a lens array for a scanning system provided so that a concave portion provided on one surface of the glass substrate corresponds to a concave portion provided on the other surface An optical apparatus comprising an electro-optical device to which a lens array is applied.

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