JPS59127017A - Optical scanner - Google Patents

Abstract

PURPOSE:To form one continuous scanning line of enlarged projection or photodetection areas of arrays of optical scanning elements on a scanning surface by using plural optical scanning element arrays, an image-forming lens array, a convergent luminous flux deflecting member and a divergent luminous flux deflecting member in combination. CONSTITUTION:An optical scanning element arrays 2, a part 4a of the lens array 4 of lens systems l1-l3 which couple the optical scanning element array 2a optically with a projection or photodetection area 7a on the scanning surface F in charge of the optical scanning element array, a convex lens 5a arranged on the end surface of the lens array 4 on the side of the optical scanning element array 2a, and a concave lens 7a arranged on the end surface of the optical scanning element array 2a on the side of the scanning surface F in a couple with the convex lens 5a are grouped. Imaginary images on the optical scanning element array 2a and area 7a on the scanning surface F meet the requirements of the unmagnified and erected real image projection of the lens array 4a, so the optical scanning element array 2a arranged at a body surface position O2 on the convex lens 5a is projected as an enlarged image on the projection area 7a at a position I2 on the scanning surface F while enlarged by the convex lens 5a and concave lens 6a respectively or photodetected while the range of the area 7a is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the construction of an optical scanning device consisting of a multiplicity of arrays of optical scanning elements used as read heads.

Optical scanning element arrays, which are constructed by integrating a large number of optical scanning elements, are used in large numbers as writing heads for printers or heads for reading information, and many types with different principles are known.

For example, an integrated array of light-emitting diodes that emit light in response to an electrical signal is known as an LED array, and an array made of a magnetic or electro-optical effect substance whose polarization state can be changed in response to an electrical signal. Elements configured in a pixel shape, integrated and arrayed are arranged between two polarizing plates arranged in a crossed nicol state, and transmission and blocking of light through the pixel-shaped material is controlled by electrical signals. Various gate arrays are also known.

For example, an optical gate array called LISA has a structure in which thin film magnetic garnet is integrated into pixels, and the plane of polarization is rotated under the action of heat and a magnetic field. The product is well known. Others: lead, lanthanum, zircon
Optical gate arrays utilizing the electro-optic effect of titanate ceramics or liquid crystals are also well known.

On the other hand, as an information reading head, silicon photo
A charge transfer type reading element called a diode array or COD is well known.

However, the well-known optical scanning element arrays described above are all formed on a single crystal substrate, and the pixels are 0, 1.
It has a structure in which it is arranged and integrated at a fine pitch of around mrn. Therefore, although its maximum length is limited by the dimensions of the single crystal substrate, it can be processed into pixel shapes and made into an array without reducing the rejection rate due to defects in materials, processing, etc.
It is not easy to manufacture optical scanning element arrays with the typically required long scan lengths.

Because of such manufacturing constraints, the most commonly used paper widths using optical scanning elements, 210-21 (
In order to cover LSS, conventional optical scanning devices use °,
For example, in the method described in Japanese Patent Application Laid-Open No. 57-67957, a plurality of light emitting diode arrays A n pieces are arranged alternately in a staggered manner on each of the left and right substrates S0゜S, and these are arranged as two fiber lens arrays L□,
L, the light emitting diode array images from A□ to An are projected and imaged on the same scanning i'ffl in a continuous straight line in the direction perpendicular to the plane of the paper without any gaps. .

Such a configuration has the advantage of being able to form a scanning line of a desired length, but it requires at least two sets of fiber lens arrays, which not only complicates the configuration but also increases the volume. Further, there are problems such as the optical adjustment being complicated and requiring high adjustment accuracy.

In addition, in such a configuration, if the optical scanning element array is a light gate array as described earlier, two light sources for illumination are also required, which further increases the size of the device. .

Another conventional example is to arrange a plurality of light gate arrays in a straight line, and enlarge and project them onto a scanning surface using a projection optical system consisting of a spherical lens, so that the images of each light gate array form a continuous straight line. Some devices are configured to form an image without any need for image formation.

FIG. 2 is an explanatory diagram of the configuration, and shows A□ to A.

is each optical gate array, and this example shows a case where five optical gate arrays are arranged. L0 to L are spherical projection lenses provided on the scanning surface F side corresponding to the respective optical gate arrays A0 to A6, and ■, to ■ are spherical projection lenses formed on the scanning surface F by the spherical projection lenses L0 to L. Projected images of the light gate arrays A1 to A, 00 to G5 are glass plates for guiding illumination light to each of the light gate arrays 80 to A5, and LG is shown in each of the light gate arrays A0 to A. A part of a light guide for guiding light from an omitted light source lamp is shown.

The support portion is necessarily constructed to be larger than the optical scanning elements or optical gate array, so that the optical scanning elements cannot be continuously arranged in a straight line, and as shown in the figure, between adjacent optical scanning element arrays, That is, an open time occurs between the optical gate arrays A□ to A5. Therefore, by using the spherical projection lenses L□-L6 provided corresponding to the respective optical gate arrays A□-A, the light gate arrays A□-A are
, each enlarged optical image is projected onto the scanning plane F, and the process, ~
As shown in Fig. 1, a linear scanning line having a desired length is obtained with the ends of each magnified image touching each other. In such a conventional configuration, the first
Unlike the conventional configuration explained in the figure, there is no need to arrange the optical scanning element arrays in a staggered manner, so it has the advantage of easy adjustment. There is AI4, which not only requires a complicated configuration but also is expensive, and also requires a larger device.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and difficulties, it is an object of the present invention to provide a simple and compact structure that can form a continuous linear scanning line on a scanning surface using a plurality of optical scanning element arrays; It is also an object of the present invention to provide an optical scanning device whose optical adjustment is easy.

The optical scanning device of the present invention includes a plurality of optical scanning element arrays arranged linearly at appropriate intervals, and an imaging lens array for optically coupling each optical scanning element array with a scanning surface. , a light flux deflecting member disposed on at least one of the optical scanning element array side and the scanning surface side of the imaging lens array, and the optical beam deflecting member is arranged on at least one side of the optical scanning element array and the scanning surface side of the imaging lens array, The area obtained by enlarging the target projection area or light receiving area by the imaging lens array, and correcting the deviation of the area in each of the optical scanning element arrays due to this expansion by the light beam deflecting member, This is characterized in that it is configured to form one continuous scanning line.

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 3 is a configuration diagram showing an example of an embodiment of the present invention, and
, lb, 10 indicate each optical scanning element array section.

This embodiment will be explained below as one for writing.

The optical scanning element array parts 1a, ib, 1c include optical scanning element arrays 2a, 2b, 2 each including a plurality of optical scanning elements such as light emitting diodes 1 or optical gates.
c is formed on each of the support substrates 8a, 3b, and 3c, including a scanning circuit (not shown) and the like. Reference numeral 4 denotes an imaging lens array, in which a microlens system in which columnar lenses called Everod lenses or fiber lenses, or small-diameter spherical lenses are arranged in multiple stages, is placed opposite to the optical scanning element arrays 2a, 2b, and 2c. The optical scanning element arrays 2a and 2b of each optical scanning lens array 4 are arranged in a continuous parallel arrangement.

A converging light beam deflecting member is placed on the 2C side in correspondence with them. Also, ea, ob, and ac are lens array 4
These beam deflecting members are diverging beam deflecting members having opposite characteristics to the beam deflecting members disposed on the scanning surface F side of the optical scanning element array 2 a e 2 b + 20.
a, , arranged to match C8.

The imaging lens array 4 also has the scanning surface F and the optical scanning element array jja, 2b, 2Cj.
The optical scanning element arrays 2a, 2b are provided at positions closer to the optical scanning element arrays 2a, 2b, 2c than the intermediate position with respect to the plane formed by the optical scanning element arrays 2a, 2b.

The imaging lens array 4, each optical The positional relationship between the scanning element arrays 2a, 2b, 20 and the scanning plane F is set.

To explain the optical/semi-scanning element array sections 1a, lb, and lc in more detail, each support substrate aa.

For example, ceramic substrates are used as 3b and 3C, and optical scanning element arrays 2a and 2b are formed on these substrates.

2C is formed, and has a configuration in which electrodes and lead wires for applying scanning signals and recording signals are drawn out, and in some cases, a semiconductor circuit for performing scanning drive is integrally attached on the substrate. It is being When the optical scanning element arrays 2a, 2b, and gc are light emitting diode arrays or optical gate arrays, these arrays are formed on a single crystal plate, but the length of the array is limited to 1 due to manufacturing technology constraints.
The limit is around 210 to 21 inches, which is generally required for optical scanning devices for printers and reading devices.
It is difficult to obtain a scanning width of 6 mm with a single optical scanning element array. In addition, each optical scanning element array section 1a, lb
, 10, the holding substrate 8a.

Each optical scanning element array 2a cannot be fabricated by arranging optical scanning elements to the ends of sb and ac.

As explained earlier, it is impossible to arrange the elements 2b and 20 closely in a straight line.

Therefore, in the present invention, as shown in the figure, an imaging lens array 4 and its optical scanning element array 2a are used.

The light beam deflecting members 5a, 5b are disposed on at least one of the 2b, 20 side and the scanning surface F side.

By combining 5C or 6a, 6b, 60, each of the optical scanning element arrays za, zb.

The optical projection area or light receiving area 7a, jb, 70 on the scanning plane F of 2C is expanded as shown in the figure without image shift to form one continuous scanning line. This is what I did. In this embodiment, as shown in the figure, the optical scanning element array 2a of the imaging lens array 4 is
, 2b, 20, correspondingly convergent beam deflecting members 5a, 5b, 5C, and divergent beam deflecting members 6ae, 6ba, 6 on the scanning surface F side.
This shows a configuration in which 7at7b is placed.
, 7c correspond to enlarged erect images of the optical scanning element arrays 2a, 2b, and 20.

To explain the operation of the structure of the present invention as described above,
The ode to obtaining an enlarged royal real image using a machi imaging lens array will be explained.

FIG. 4A is an explanatory diagram of a known general usage state of an imaging lens array. La, Lb, and Lo are microlens optical systems (hereinafter referred to as The term "lens" is simply used to include columnar lenses.The imaging lens array consists of these lenses La, L.
b.L.

As shown in the figure, they are arranged in parallel in a straight line. Assuming that arrow 01 indicates a part of the optical scanning array, an erect real image of equal magnification is formed by lens La as Io. If the optical axis on the light output side is X' with respect to the optical axis X on the light input side of the lens La, the tip of the arrow O□ is in contact with the optical axis X, so the magnification of the erect real image,
The tip of the image is also in contact with the optical axis X', and the size of the erect real image is the same as that of the arrow 0□.

Similarly, lens L. The equal-sized erect real image by These equal-sized erect real images I, II□' overlap and are recognized as one image, and a equal-sized erect real image corresponding to the arrow O is obtained.

Figure 4B shows a situation in which the optical scanning element 01, indicated by the arrow, is brought close to the imaging lens array in order to form an enlarged image using the imaging lens array shown in Figure A. It is. In this case, as for the lens La, an enlarged erect real image shown by arrow 02 is formed. That is, in this case, since the tip of the arrow 02 is in contact with the optical axis X, the tip of the magnifying imager 2 is also in contact with the optical axis X'. Similarly, lens L.

The enlarged erect real image of arrow O is formed on the same plane as the enlarged erect real image 2 by the lens La, but since the rear end of arrow 02 is in contact with the optical axis y, its enlargement is The rear end of the erected real image I,/ also comes into contact with the optical axis y'. As a result, the lens La is removed. Enlarged erect real image 2
and 1. / overlaps as shown in the figure', and the enlarged erect real image of arrow 02 on the image plane will be recognized as a multiple image or a blurred image, and there is a problem that a normal enlarged erect real image cannot be obtained. .

In response to this problem, the present inventors have invented a variable magnification optical image projector which is capable of normally projecting a variable magnification image by the lens array by combining an imaging lens array and a light beam deflection member. The content of the invention is detailed in Japanese Patent Application No. 155789/1989 filed by the applicant. The present invention utilizes the variable magnification optical image projector, which is currently being applied for, to expand the optical projection area or light receiving area on the scanning surface by a plurality of discontinuously arranged optical scanning element arrays, and to perform one continuous scanning. It is designed to form a line. Therefore, the effects of the structure of the present invention will be explained, including the technology applicable to the present invention described in the specification of Japanese Patent Application No. 57-155789.

FIG. 5 is an explanatory diagram of the operation of the variable magnification optical image projector of the present application, that is, the optical system formed by the combination of the imaging lens array and the light beam deflection member in the present invention. Same 1mA
, B, and O, the same parts as those of the conventional one shown in FIG. 4 are designated by the same reference numerals. And lens La
is a lens facing the center of each optical scanning element array, and each center ff501 e of each optical scanning element array 2a, 2b, 2C in the imaging lens array 4 in FIG.
02t Corresponds to the lenses arranged on the OB. Lens L. indicate lenses located away from their center lines C0°C2, C8 in the same optical scanning element array. There are also lenses between the nozzles La and Lo, but these are not shown. The lenses La and Lo are linearly arranged in parallel to form an imaging lens array 4.

Figure A shows converging and diverging light beam deflecting members disposed on the optical scanning element array side and the scanning surface side of the lens array 4, respectively, such as prisms P and P so that the deflection directions are opposite to each other. ' is shown. The image by the lens La of the optical scanning element array indicated by the arrow O8 can be indicated by , as in the conventional case. On the other hand, lens L. The optical axes y and y' of the lens L will be deflected as shown by the prisms P and P'. By appropriately setting the deflection angles of the prisms P and P', the image of the optical scanning element array indicated by 02 can be formed at the positions of ■ and ', and its size can be made equal to ■2. I can do it.

Light beam deflecting members for this purpose, namely prisms P and P'
The deflection angle of is determined by the projection magnification of the image, the respective distances from the end face of the lens array to the optical scanning element array and the scanning plane,
and lens L. The closer the angle is to the center lens La, the smaller the deflection angle will be.

Actually, the lens is La. A lens array 4 is formed by having a large number of lenses between them, and a large number of lenses having different deflection angles correspond to the individual lenses.
, p', but if we differentiate into a large number of prisms P and P' in this way, we will end up with the third prism.
As shown in the figure, light beam deflection members 5a, 5b on the optical scanning element array 2a, 2b, 2c side of the imaging lens array 4,
5c has a convex lens-shaped cross section, and is a light flux deflecting member 6a, 6b on the scanning surface F side.

6C has a cross-sectional shape of a concave lens. In other words, the light beam deflecting members 5a, 5b, 5c or 6a+6b,
As 6c, individual optical scanning element arrays 2a, 2b,
The optical scanning element inserted on the optical scanning element array side with the axis c1°C2, C8 passing through the center of the optical scanning element 20 as the optical center has a focusing property, that is, it has a convex lens-like cross-sectional shape.
The lens to be inserted and arranged on the scanning surface side may have a diverging property, that is, a concave lens-like cross-sectional shape.

In the configuration of the embodiment of the present invention shown in FIG.
2b and 2c are enlarged and projected onto the scanning plane F so that adjacent projected images are connected to form one linear scanning line.

The same effect as in the previous embodiment can also be achieved by inserting the light beam deflecting member only on one side of the lens array 4.

FIG. 5B is a diagram illustrating the operation of another embodiment of the present invention in which a prism P is inserted as a focusing beam deflecting member only in each optical scanning element array of the lens array 4.

In this case, the lens L is used only on the ' side where the prism P is present. The optical axis y of is bent toward the center, and image processing 2 t and image processing 2 ′ by each lens Lal Lo are formed as enlarged images overlapping at the same location on the scanning plane. FIG. 5C is an explanatory diagram of another embodiment of the present invention in which a prism P' is disposed as a diverging light beam deflecting member only on the scanning surface side of the imaging lens array 4. In this case, lens L. The optical axis y' on the side of the scanning surface is deflected, and a single scanning line is formed by the same action as in the case of A and B in the same figure. Note that the configuration of the embodiment shown in FIG. This is advantageous in that it can take up a sufficient amount of holding space.

As shown in FIGS. 5B and C, the prism P or P
1, that is, the structure in which the light beam polarizing member is arranged only on one side of the lens array 4 has the advantage that the structure is simpler than the structure in which it is arranged on both sides as shown in FIG. In general, as the deflection angle of the optical axis increases, optical aberrations due to the presence of a beam polarizing member increase, and as the optical axis is tilted, the optical path length increases, resulting in image blurring. Although there is a risk of deterioration, there is no problem and it can be effectively implemented when used for applications where the projection area or light receiving area of an optical scanning element array is sufficient, where the polarization angle by the light beam polarizing member is small. .

As explained earlier, the light beam polarizing member used has a cross-sectional shape of a convex lens for the eastern prefectural type, and a concave lens-like cross-section for the diverging type. A convex or concave lens with a diameter approximately equal to or larger than that of the optical scanning element array formed into a unit length may be cut to a desired width, or a cylindrical lens with a convex or convex lens shape may be used. A concave lens-like cross section may be used, or a Fresnel lens may be used.

FIG. 6 shows a condensing light beam deflecting member 5a having a convex lens-like cross section in the configuration of the embodiment shown in FIG.

5b, 5c and the diverging beam deflecting members Qa, 6b, 60 having a concave lens-shaped cross section, light beam deflecting members Ba, Bb, Q each having a 7-lens lens-shaped cross section.
This shows an example of a configuration in which c, 9a, and 9b19C are arranged. With this configuration, each light beam deflection member 8a.

Since the thicknesses of Bb, Bc, 9a19b, and 9c can be made almost uniform over the entire surface, not only can the influence of increase in optical path length due to these beam deflecting members be reduced, but also the optical path length can be kept at a constant value. There are advantages. Moreover, since the light beam deflection members can be brought sufficiently close to the imaging lens array 4 at the same time, the light beam deflection members sa, sb*s
The distances from c to the optical scanning element arrays 2a, 9b, 2C and from the diverging beam deflection members ga, 9b, 9c to the scanning surface Y are longer, and therefore a smaller beam deflection angle is desired. It is possible to obtain the offset positions α and α' of , and there is also the advantage that the occurrence of color differences etc. can be suppressed to a small level. In addition, each of the seven requil lenses 8a, 8b, and 8C used as the condensing light beam deflection member and the diverging light beam deflection member
,9a,9b,90G! Even if it has a light beam deflection effect in both directions perpendicular to the scanning line, like a spherical lens, and like a cylindrical lens, it only has a light flux deflection effect in the plane that includes the scanning line. However, since the width of the scanning line usually has a very small value (around 0-1 gates), both can be used almost equally as constituent elements of the present invention.

As described above with reference to several examples of various forms of the one-beam deflection member in the present invention, the action of the light flux deflection member in the present invention is based on the optical scanning element of each lens constituting the imaging lens array 4. Arrays 2a, 2b,
mC1, , <), , 0 passing through the center of each of 2c
．． The optical axis is deflected in accordance with the distance from the end toward the end. Therefore, the bending action has almost no effect on the imaging action of each lens constituting the imaging lens array 4.

However, in carrying out the present invention, if the light beam deflection member has a thickness t and is formed of a material with a refractive index n, the optical path length can be changed by inserting the light beam deflection member (
It is necessary to set the positions of each member constituting the enlarged projection optical system with the imaging lens array 4 as the center, taking into account that the length will be longer by n-1)t.

In the embodiments shown in FIGS. 3 and 6, the imaging lens array 4 was constructed by arranging lenses over the entire length of the desired scanning line. Optical scanning element arrays 2a, 2b, 2C!
In other words, in FIG. 6, the diagonally shaded portions indicated by v and v' are the portions of the light beams formed at the ends of the adjacent optical scanning element arrays 2a and 2b. Since the light beam does not enter the area of the imaging lens array 4 indicated by U in the figure, which is transmitted to the scanning surface F by the lens array 4, no lens may be provided in this area. Therefore, each optical scanning element array 2a utilizes the unnecessary area U.

What is necessary is just to provide a structure so that members may be provided and held separately.

In order to adopt such a configuration, in order to obtain the area indicated by U, it is necessary to provide a light beam deflecting member on the scanning surface F side of the lens array 4, and on the optical scanning element array side of the lens array 4. The presence or absence of the light beam deflecting member is not related to the unnecessary area U.

FIG. 7 shows the configuration of another embodiment of the present invention. In this embodiment, each optical scanning element y-ray section 1a, l
b, 1c with lens array 4, each independent plurality of optical scanning blocks 10a.

10b and 100, and the necessary number of optical scanning blocks to form a scanning line of a desired length on the scanning plane F are closely arranged.

That is, individual optical scanning blocks]Oa.

10b, the IOC has almost the same configuration, and as shown in the figure, an optical scanning element array 2 constituting the optical scanning element array section 1 and an imaging device provided opposite to the optical scanning element array 2. A lens array 11, a convex 7-lens lens type light beam deflecting member 5 disposed on the optical scanning element array 2 side, and a concave Fresnel lens type light beam deflecting member disposed on the scanning surface F side of the lens array 11. 6 are integrally constituted. Then, the plurality of optical scanning blocks IQa, 10b, Inc configured in this manner are subjected to each enlarged projection *7a, 7b,
7c are arranged closely to form one continuous scanning line of a desired length. Furthermore, the sequential optical scanning blocks do not necessarily have to be closely arranged, but only need to form one continuous scanning line.

For example, a drive circuit for arranging optical scanning blocks such that adjacent scanning line forming areas formed by individual optical scanning blocks formed by sequential optical scanning blocks slightly overlap each other, and driving the optical scanning element of each optical scanning block. If the configuration is such that substantially one scanning line is formed by signal processing, there is an advantage that there is no need to closely arrange successive optical scanning blocks with high accuracy.

In such a configuration, if the individual optical scanning blocks are precisely optically adjusted in advance, optical scanning with an arbitrary scanning length can be achieved by simply arranging these optical scanning blocks. There is an advantage that the scanning device can be easily realized.

In each of the above embodiments, the explanation has been made assuming a light emitting diode array or a gate array as the optical scanning element array because it is assumed that the optical scanning element array is used for a printer. It's not something you do. For example, if a light receiving element array made of photodiodes or phototransistors is used as the optical scanning element array, it can of course be used for information reading; such embodiments are also included in the present invention. It is. In this case, the scanning surface F in each of the above embodiments corresponds to the document surface, and the information of each light receiving area for each optical scanning element array on the scanning line on that surface is transmitted by each corresponding optical scanning element array. It will be read.

As described above in detail in each embodiment, according to the present invention, the optical projection area or the light receiving area on the scanning plane of a plurality of discontinuously arranged optical scanning element arrays can be formed using a relatively simple configuration. , not only can it be easily formed as a single continuous scanning line, it can also be made smaller than conventional ones, and it is not only easy to form blocks for each optical scanning element array, but also allows for optical adjustment. A relatively simple and high performance optical scanning device can be obtained.

In addition, in the case where the optical scanning element array is divided into blocks, it is possible to have a structure in which the number of optical scanning blocks corresponding to the desired scanning length is closely arranged, and each optical scanning block is Since optical adjustments can be made in advance, there are advantages such as a highly accurate optical scanning device having a desired scanning length can be easily provided as required.

[Brief explanation of the drawing]

1 and 2 are schematic configuration diagrams for explaining different conventional examples, FIG. 3 is a configuration diagram showing an example of an embodiment of the present invention, and FIG. 4A is a well-known image forming method. Figure 5 A, B and C are diagrams for explaining the formation of a 1-magnification erect image using a lens array. 6 is an explanatory diagram of a modification of the configuration of the embodiment of FIG. 8, and FIG. 7 is an explanatory diagram of the configuration of another embodiment of the present invention. It is an explanatory diagram. 1, la, lb, 10... optical scanning element array section 2.2a, 2b, 2C... optical scanning element array a
+ 8 a t 8 b, a c , , Support substrate 4.11...Imaging lens array 5.5a, 5b, 50 and 6.6a, 6b. 6C... Light beam deflection members 7a, 7b, 7C...Projection area or light receiving area Ba, Bb, BC of each optical scanning element array...Convex Fresnel lens shaped light beam deflection members 9a, 9b , 9c...Concave lens type 7-lens nose-shaped light beam deflecting member] Oa, 10b, 10Cj... Optical scanning block C!
, , 02.08-...Each optical scanning element array 2a,
2b. Center F of 2C...Scanning surface □ 0□, 0□...Optical scanning element array La, Lb, Lo...Column lens (microlens optical system) Io, I,'...1-magnification erect Real images x, x', y, y'...optical axis I2. I,'
...Enlarged erect real image P, P'... Prism (light beam deflection member) Patent applicant Olympus Optical Industry Co., Ltd. Figure 1 Figure 2 Figure 4 A B A Figure 5 0 Procedural amendment 1982 June 80 1, Indication of the case 1981 Special Patent Application No. 3025 2.
Name of the invention Optical scanning device 3, Relationship with the case of the person making the amendment Patent applicant (037) Olympus Optical Industry Co., Ltd. 7, Contents of the amendment (as attached) Figures 3, 5, and 6 in the drawings Figures 8 and 7 have been corrected as shown in the attached corrected figures, and Figures 8 and 9 have been added. (Correction) Description 1, Title of the invention Optical scanning device 2, Claim L A plurality of optical scanning element arrays arranged in a straight line at appropriate intervals, each of these optical scanning element arrays and a scanning surface An optical scanning device characterized in that the optical scanning device is configured to form a scanning line of optical projection on the scanning surface of each of the optical scanning element arrays by positioning the grooves that optically couple the optical scanning elements. 2. The optical scanning device according to claim 1, wherein the optical scanning device is configured to form a scanning line of . & A patent claim characterized in that the condensing light beam deflection member disposed on the optical scanning element array side of the lens array is composed of a convex lens, and the diverging light flux deflection member disposed on the scanning surface side is composed of a concave lens. The optical scanning device according to the range 1 or 2. 8. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the construction of an optical scanning device consisting of an array of multiple optical scanning elements for use as a writing or reading head for optical recording. Optical scanning element arrays, which are constructed by integrating a large number of optical scanning elements, are used in large numbers as writing heads for printers or heads for reading information, and many types with different principles are known. For example, an integrated array of light-emitting diodes that emit light in response to an electrical signal is known as an LED array, and an array made of a magnetic or electro-optic effect substance that can change the polarization state in response to an electrical signal. Integrates unit elements configured by arranging electrodes in a pixel shape,
Various optical gate arrays are also known, in which the gate array is arranged between two polarizing plates arranged in a cross-niffle state, and the transmission and blocking of light through the pixel-shaped unit elements is controlled by electric signals. It is. For example, an optical gate array called LISA has a structure in which electrodes are integrated into a thin film magnetic garnet in the form of pixels, and the plane of polarization is rotated under the action of heat and a magnetic field. It is well known as a product of ValVOGm bH. In addition, optical gate arrays that utilize the electro-optic effect of lead-lanthanum-zircone-titanate ceramics or liquid crystals are also well known. On the other hand, as an information reading head, silicon photo
Charge transfer type reading elements called diode arrays or CCDs are well known. , is arranged and integrated at a fine pitch of around 1 ms. Therefore, the maximum length is limited by the dimensions of the single crystal substrate, or it can be manufactured without increasing the rejection rate due to defects due to materials or processing when processing into pixel shapes and forming an array. Due to their limited nature, it is not easy to manufacture optical scanning element arrays with the typically required long scan lengths. Due to such manufacturing constraints, the most commonly used paper widths using optical scanning elements are 210-216 mm.
In order to cover this problem, in conventional optical scanning devices, for example, as shown in FIG. are alternately arranged in a staggered manner on each substrate S0°S, and these are connected to two 7-eye lens arrays L1. L
2, the light emitting diode array images A0 to An are projected and formed in a continuous straight line in a direction perpendicular to the plane of the paper without any gaps on the same scanning plane. Although such a configuration has the advantage of being able to form a scanning line of a desired length, it requires at least two sets of 7-eyeper lens arrays L, L2, which not only makes the configuration complicated; In addition, there are problems such as the volume becomes large and the optical adjustment is complicated and high adjustment accuracy is required.In addition, in such a configuration, the optical scanning element array is not the same as the optical gate array described earlier. In the case of There is also a structure in which each optical game F array image is formed in a continuous straight line without gaps by enlarging and projecting onto the scanning surface using a projection optical system consisting of the following. FIG. 2 is an explanatory diagram of the configuration, and shows A□ to A. is each optical gate array, and this example shows a case where five optical gate arrays are arranged. L□-L5 are spherical projection lenses provided on the scanning surface F side corresponding to the respective optical gate arrays A0-A, and 1□-I are the spherical projection lenses formed on the scanning surface F by the spherical projection lenses L0-L5. Projected images of the optical gate arrays A0 to A4, G1 to G6 are glasses and glass plates for guiding the illumination light to each of the optical gate arrays A to A, and LG is the projection image of each of the optical gate arrays A to A.
5 shows a part of a light guide for guiding light from a light source lamp (not shown). Each of the optical gate arrays A□ to A uses glass plates G□ to G5 as supports, respectively. Therefore, due to its manufacturing, the support portion is necessarily larger than the optical scanning element array, that is, the optical gate array, and therefore the optical scanning elements on each glass plate G□ to G5 are continuously arranged in a straight line. As a result, a gap is created between adjacent optical scanning element arrays, that is, between optical gate arrays 0 to A5, as shown in the figure. Therefore, the optical images from the optical gate arrays A□ to A6 are each enlarged and projected onto the scanning plane F by the spherical projection lenses L0 to L5 provided corresponding to the optical gate arrays A□ to A5, respectively. As shown by . . . , a linear scanning line having a desired length is obtained with the ends of each magnified image adjoining. This type of conventional configuration has the advantage of deep adjustment because it is not necessary to arrange the optical scanning element array in a staggered manner as in the conventional configuration explained with reference to FIG. This requires a number of spherical projection lenses corresponding to the number of scanning element arrays, which not only complicates the configuration but also makes it expensive, and the apparatus also becomes larger. In addition, in a magnifying optical system using a spherical lens optical system as described above, the brightness of the element image located at the end of the projected image is determined by the angle of inclination of the light beam connecting the center of the spherical lens and the end element.
It is unavoidable that the light becomes darker in proportion to the power of the light, which is influenced by the so-called cosine fourth power law, and therefore, it is difficult to form a scanning line that is uniform in light density. An object of the present invention is to: - In order to solve the above-mentioned problems and difficulties, a configuration that can form a continuous linear scanning line on a scanning surface using a plurality of optical scanning element arrays can be simplified and miniaturized. It is an object of the present invention to provide an optical scanning device that is easy to adjust optically. The optical scanning device of the present invention includes a plurality of optical scanning element arrays linearly arranged at appropriate intervals, and a lens array for optically coupling each optical scanning element array with a scanning surface. That's the lens. a plurality of condensing light beam deflection members disposed between each of the lens array and the optical scanning element array; and a pair of the condensing light beam deflection members disposed between the lens array and the scanning surface. a plurality of diverging light beam deflection members respectively arranged to make a virtual image formation position by the condensing light beam deflection members of the optical scanning element array, and a receiver of the optical scanning element array having a plurality of light beams on the scanning surface. - positioning so that the virtual image formation position by the diverging light beam deflection member in the optical projection area or the light receiving area corresponds to the object plane and image plane positions of the lens array that satisfy the same-magnification erect real image projection conditions, respectively; , the optical projection area or the light receiving area on the scanning surface of each of the optical scanning element arrays is expanded to form one continuous scanning line. Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 8 is a configuration diagram showing an example of an embodiment of the present invention, and
, lb, and 10 each indicate an optical scanning element array assembly. This embodiment will be explained below as one for writing. The optical scanning element array assemblies 1a to IC have optical scanning element arrays 2a to 2C formed by a plurality of optical scanning elements, such as light emitting diodes or optical gates, on each support substrate 8a to 3C, including a scanning circuit (not shown), etc. The structure is as follows. 4 is a lens array with a length that covers the entire length of the scanning line, for example, a columnar lens called a Rondo lens or a fiber lens, or a microlens system in which multiple stages of small diameter spherical lenses are arranged continuously in parallel. The optical scanning element array 2a to 2C is inserted between the optical scanning element arrays 2a to 2C and the scanning surface F so as to optically couple them. Reference numerals 5a to 5C designate condensing light beam deflecting members, such as convex lenses, arranged on the optical scanning element arrays 2a to 2C side of the imaging lens array 4 in correspondence with the respective optical scanning element arrays. Further, 6a to 6C are diverging light beam deflecting members, such as concave lenses, arranged on the scanning surface F side of the lens array 4 to form a pair with each of the convex lenses 5a to 5C, and the center of each of these light beam deflections 2C is They are arranged to correspond to 00 to C8, respectively. The lens array 4 is provided at a position closer to the optical scanning element arrays 2a to 20 rows than the intermediate position between the scanning plane F and the optical scanning element arrays 2a to 2C. The scanning element arrays 2a to 20, the convex lenses 5a to 50% lens array 4, the concave lenses 6a to 6C, and the scanning surface F are composed of convex lenses 5a to 20, as will be described in detail later.
The virtual image forming position of each optical scanning element array 2a to 2C by 5C and the virtual image forming position of each projection area 7a to 7C on scanning plane F by concave lenses 6a to 6C satisfy the same-size erect real image projection condition of lens array 4. It is positioned so that it coincides with the object plane and the image plane, respectively. Also,
The intervals between the optical scanning element arrays 2a to 2C are such that the projected images of the optical scanning element arrays 2a to 2C enlarged and projected onto the scanning surface F by the optical systems configured as described above are adjacent to each other and are continuous. An appropriate distance, lli, that can form one scanning line is set. To explain the optical scanning element array assemblies 1a-IC in more detail, for example, a ceramic substrate is used as each of the supporting substrates 8a-8C, and the optical scanning element arrays 2a-20 are formed on this substrate. It has a configuration in which electrodes and lead wires for applying recording signals and the like are drawn out, and in some cases, a semiconductor circuit for performing scanning drive is integrally mounted on the substrate. When the optical scanning element arrays 2a to 2C are light emitting diode arrays or optical gate arrays, these optical scanning element arrays are formed on a single crystal plate, but the length of the optical scanning element array is limited by manufacturing technology. It is difficult to obtain a scanning width of about 210 to 216 mm, which is generally required for optical scanning devices for printers and reading devices, with a single optical scanning element array. Furthermore, since each of the optical scanning element array assemblies 1a to IC cannot be manufactured by arranging the optical scanning elements to the ends of the holding substrates 8a to 8C, the optical scanning element arrays 2a to 20 are arranged in close contact with each other in a continuous manner. As explained above, it is impossible to arrange them in a straight line. Therefore, in the present invention, as shown in the figure, a lens array 4, an optical scanning element array 2a of the lens array 4,
2b, 2c side and the scanning surface F side, condensing light beam deflection members such as convex lenses 5a to 5C, and diverging light beam deflection members such as By combining each pair of concave lenses 6a to 6C, the optical projection areas 7a, 7b, 70 on the scanning plane F of each of the optical scanning element arrays 2a, 2b, 2c are enlarged as shown in the figure to form one continuous line. It is configured so that a scanning line is formed, and in this case, F a + 7 b + 70 corresponds to an enlarged erect real image of the optical scanning element arrays 2a, 2b, and 20. Next, we will explain the effect of enlarging the projected image of the optical scanning element array by the configuration of the optical system in the apparatus of the present invention, and then explain the problems in the case where the enlarged erect real image 1 is obtained by the lens array. - FIG. 4A is an explanatory diagram of a known general usage state of the lens array. L+a+ "b l Llo is a gradient index columnar lens, also called a rod lens or fiber lens, in which the refractive index changes from the periphery toward the center, or a microlens optical system consisting of multiple stages of small diameter spherical lenses ( Below, including the columnar lens, it is simply "
lens). Such a lens array is
These lenses La, Lb, and Lo are arranged in parallel in a straight line as shown in the figure. Now, assuming that the arrow O□ indicates a part of the optical scanning element array, an erect real image of equal magnification is formed by the lens La as . If the optical axis on the light output side is x' with respect to the optical axis X on the light input side of lens La, the tip of the arrow 0□ is in contact with the optical axis X, so the tip of the same-size erect real image is also Optical axis
, and its equal-sized erect real image I□ and arrow 0□ have the same size. Similarly, lens L. A life-size erect real image is also formed as an image, and after the arrow 0 and its life-size erect real image 1 □, the result is each life-size royal image □, as shown in the figure. ■, ′ overlap and are recognized as one image, arrow 0□
An erect real image of equal size corresponding to is obtained. Figure 4B shows a situation in which the optical scanning element 0□, indicated by an arrow, is brought close to the imaging lens array in order to form an enlarged image using the imaging lens array shown in Figure A. It is something that In this case, regarding lens La, arrow 02
An enlarged erect real image 2 is formed. That is, in this case, since the tip of the arrow 02 is in contact with the optical axis X, the tip of the enlarged image 1□ is also in contact with the optical axis X/. Similarly, lens L
. The enlarged erect real image 12 indicated by the arrow 02 is formed on the same plane as the enlarged erect real image 12 indicated by the lens La. Although the rear end is in contact with the optical axis y, the rear end of the enlarged erect real image, l, is also in contact with the optical axis yl. As a result, the lens La is removed. In the enlarged erect real image, the images 2 and 2/ do not overlap as shown, and the arrow 0. The enlarged erect real image will be recognized as a multiple image or a blurred image, and there is a problem that a normal enlarged royal real image cannot be obtained. As explained above, in an optical system using a lens array, even though a variable magnification image can be formed by each individual lens, the lens array as a whole forms a normal variable magnification image. I can't do anything. - On the other hand, the configuration shown in the first part shows one method of making it possible to project an enlarged image using a lens array. In the same figure, /, , ! Reference numeral 2.18 indicates a lens system capable of projecting an erect real image of equal magnification, such as a fiber lens, which is assembled to form the lens array 4. When the object 0 is placed at a position where the lens array flaw satisfies the condition for projecting a 1:1 erect real image, a 1:1 erect real image □ is formed on the exit side of the lens array 4. Therefore, on the end surface of the lens array 4 between the lens array 4 and its imager,
When the concave lens 6 is placed, the light rays forming the same-magnification erect real image 1 as shown in the figure will diverge in the direction of m on the image side.
The resulting image is formed as an enlarged image 2 at a position farther away from the original 1-size Royal Real Image □. The relationship between these images 11' and 1 is such that the virtual image formed when (2) is viewed through the concave lens 6 is 10. Therefore, if the actual image plane is placed at the position of the enlarged image plane 2, the virtual image plane of the 8 planes of the image plane formed by the concave lens 6 becomes
The real image processing surface 8 may be positioned so as to coincide with the image plane of the same-magnification erect real image projection of the lens array 6. An enlarged image projection optical system based on this principle is disclosed in Japanese Patent Application Laid-Open No. 54-154148.
It is disclosed in the publication No. 1 and is known. Alternatively, it is also possible to project an enlarged image by combining a convex lens and a lens array. 6th
The figure is an explanatory diagram of its configuration and operation. In other words, a plurality of lens systems l□r lx capable of projecting a same-size erect real image
A convex lens 5 is arranged on the end surface of the ring body 02 side of the lens array 4 consisting of +/8. When the object 02 is viewed through the convex lens 5 arranged in this manner, an enlarged virtual image 0□ is obtained. The convex lens 6 and the object 0 . By positioning the object O8, an enlarged image 1□ of the object O8 can be obtained at a position that satisfies the same-magnification erect real image projection condition of the lens array 4. In addition, Fl + FB in FIG. 5 is the focal point of the concave lens 6, h
□ indicates the principal plane of the concave lens 6, and F and □ in FIG. 6 indicate the focal point and principal plane of the convex lens 5, respectively. However, the concave lens 6 shown in FIGS.
Alternatively, if an optical system combining the convex lens 5 and the lens array 4 is used to obtain an enlarged image of the optical scanning element array, thereby forming a scanning line with a desired scanning line length, the following can be done. The optical systems shown in FIGS. 1 and 6 cannot be used as they are because of various inconveniences such as the following. That is, to explain the case where an optical scanning device similar to the device of the present invention as shown in FIG. 7 is constructed using the configuration shown in FIG. The magnification effect is performed only by the arranged convex lenses 5a to 5C. Therefore, in order to obtain the desired magnification, it is necessary to increase the curvature of the convex lenses 5a to 5C, but increasing the curvature may increase aberrations, or the optical scanning element array facing the optical scanning element array or the optical scanning element array on the scanning surface F may increase the curvature. When the inclination angle α of the peripheral light beam with respect to the projection area becomes large, and the angular distribution of the light microdistribution characteristics and light reception characteristics of the individual optical scanning element arrays is biased,
The amount of light or light-receiving sensitivity at the periphery of the projection area or light-receiving area of the optical scanning element array is significantly reduced. Further, adjacent scanning elements located at the ends of adjacent optical scanning element arrays need to be projected so that they are adjacent to each other on the scanning plane F, but as is clear from the configuration of FIG. In order to project the adjacent optical scanning element arrays 2a to 2C onto the scanning surface F without gaps, the convex lenses 5a to 2C are used.
5C must be closely arranged with the same level of precision as the arrangement precision of the optical elements in the optical scanning element arrays 2a to 2C, and it is impossible to arrange the convex lenses 5a to 50 with such precision. It is. On the other hand, in the optical scanning device of the present invention, as explained with reference to the embodiment shown in FIG. The conventional optical system shown in FIG. 6 or FIG. The above-mentioned problem in the case of using the system is solved. Hereinafter, the effect of enlarging the projection or light receiving area of the optical scanning element array by the configuration of the optical system in the apparatus of the present invention will be explained with reference to FIG. For convenience of explanation, the figure shows the eighth
The optical scanning element array 2a in the illustrated embodiment, and the optical lens system 10 for optically coupling the optical scanning element array 2a with the projection area or light receiving area 7a of the optical scanning element array in the scanning plane F. A portion 4a of the lens array 4 consisting of ~, a convex lens 5a disposed on the end surface of the optical scanning element r-ray 2a side of the lens array 4, and an end surface of the optical scanning element array 2a on the scanning surface F side so as to form a pair with the convex lens 5a. 3 shows a portion of an optical scanning block that includes a set of concave lenses 7a arranged in FIG. In the figure, if the positions indicated by 0, 0, and - are the positions of the object plane and image plane that satisfy the same-magnification erect real image projection conditions of the lens array 4a, then the convex lens 5a is placed at the 0 position. The curvature of the convex lens 5a is selected and the convex lens 5a and the optical scanning array 2a are positioned so that a virtual image of the optical scanning element array 2a is formed. 02 indicates its position. On the other hand, the concave lens 6a selects the curvature of the concave lens 6a so that a virtual image by the concave lens 6a of the area 7a held by the optical scanning element array 5a on the scanning surface F is formed at the position □. The concave lens 6a and the scanning surface F are positioned. By configuring the optical system in this way, each virtual image of the optical scanning element array 2a and the area 7a on the scanning surface F satisfies the same-magnification erect real image projection condition of the lens array 4a. The optical scanning element array 2a disposed at the object plane position 02 of 5a can receive light by reducing the range of the area 7a through the convex lens 5a and the concave lens. However, the feature of the optical system with such a configuration is the fifth one.
Compared to the conventional magnifying optical system shown in Fig. 6 and Fig. 6, in which the lens array 4 is configured with one concave lens or a combination of concave lenses, the magnifying action of the lens is divided into the entrance side and the exit side of the lens array. Therefore, the curvature of each lens can be reduced, and the overall occurrence of aberrations can be suppressed. In addition, as shown in FIG. 8, the inclinations α and β (see FIG. 3) of the end beams of the optical scanning element arrays 2a to 2C and the respective regions 7a to 7C on the scanning surface that they have are also as follows: The problem must not occur concentratedly on one side or the other. Furthermore, as can be seen from the light beam diagram indicated by the dashed dotted line in the configuration diagram of the embodiment in FIG. The light beams X and y from the outermost elements of the element array are brought close to the element pitch in the scanning plane, but in this way, the light beams from the outermost elements of each optical scanning element array 2a to 2c are brought close enough to each other. Also, since the light beams X and y are separated from each other at a position away from the scanning plane F, the convex lenses 5a to 50. Moreover, it is possible to arrange the concave lenses 6a to 6C larger than the effective light beam, and the light beam having an aperture angle can be transmitted to the scanning surface F without substantial loss. The apparatus of the present invention utilizes the configuration of the optical system having the above-mentioned features to obtain an enlarged projection area or The light receiving areas 7a to 7C are configured to form one continuous scanning line on the scanning surface F. Although the present invention has the configuration as described above, many modifications can be made within the scope of the gist of the present invention. For example, a 7-renel lens with condensing and diverging properties may be used as the condensing light beam deflection member and the diverging light flux deflection member. In the embodiment shown in FIG. 8, the lens array 4 is one long enough to form a scanning line of a desired length. The configuration of the optical system of the apparatus of the present invention described above may be made into a flock unit. FIG. 9 shows an embodiment in which the apparatus of the present invention is constructed using the optical scanning blocks 8a18b and 80 formed into blocks as described above. Ba. sb and sc are each optical scanning block having the configuration shown in FIG. A configuration in which the projection areas or light receiving areas formed by the respective optical scanning blocks 2a to 2c are arranged so as to form one continuous scanning line, as many as necessary to form a scanning line with a length of It becomes. For example, each optical scanning block 8a is placed in a relationship in which adjacent scanning line forming areas formed by individual optical scanning blocks slightly overlap each other.
8b may be arranged so that substantially one scanning line is formed by signal processing of a drive circuit for driving the optical scanning elements of each optical scanning block sa, Bb. According to such embodiments, the individual optical scanning blocks 8
Since a to 8c can be optically adjusted accurately in advance, an optical scanning device with an arbitrary scanning line length can be created by simply arranging and configuring optical scanning blocks as necessary. It is easy to realize this, but there are disadvantages. The optical scanning element array in each of the above embodiments is as follows:
When used in a printer, for example, a light emitting diode array or a light gate array may be used, and for reading, a light receiving element array consisting of, for example, a photodiode or a phototransistor may be used. As described above in detail in each embodiment, according to the present invention, the optical projection area or the light receiving area on the scanning plane of a plurality of discontinuously arranged optical scanning element arrays can be formed using a relatively simple configuration. Not only can it be easily formed as one continuous scanning line, but it can also be made smaller than conventional ones, and a simple high-performance optical scanning device can be obtained. Furthermore, in the present invention, the principal rays from the elements constituting the optical scanning element array are emitted perpendicularly to the lens array, as can be seen from the explanation of FIG. In the configuration of the optical system using the conventional spherical lens shown above, it is possible to prevent the inevitable decrease in the end light amount due to the cosine fourth power law of the spherical lens system.
It is possible to form scanning lines with a more uniform optical field or light receiving sensitivity than in the conventional method. Furthermore, in the case where each optical scanning element array is divided into blocks, it is possible to have a configuration in which the number of optical scanning blocks corresponding to the desired scanning length is closely arranged. Since the adjustment can be made in advance, a highly accurate optical scanning device with a desired scanning length can be easily provided as required. The figures are schematic configuration diagrams for explaining different conventional examples, FIG. 8 is a configuration diagram showing an example of an embodiment of the present invention, and FIG. ``The theory of formation of a erect image'' - Figure B is an explanatory diagram of the problems encountered when forming an erect image with variable magnification. An explanatory diagram of the configuration and operation for forming a real image. FIG. 7 is an explanatory diagram of the problems when using the optical system of FIG. 6. FIG. 8 is an explanatory diagram of the configuration and operation of the optical system in the present invention. , FIG. 9 is an explanatory diagram of the configuration of another embodiment of the present invention. la, lbl 10... optical scanning element array assembly 2a, 2b, 2c... optical scanning element array aa, ab, 3c ...Supporting substrate 4.4a...
Lens arrays 5, 5a, 5k), 50...Convex lenses (condensing light beam deflection members) 6, 6a, 6b, 60...Concave lenses (divergent light beam deflection members) 7a, 7bl 70...Each optical scanning Projection area or light receiving area of element array 8a, 8b, 8c... optical scanning block 01.0
2 * OB ""Each optical scanning element array 2a, 2b
, 20 center F... scanning plane. Patent applicant: Olympus Optical Industry Co., Ltd. Figure 6
(Correction 511) Figure 7

Claims (1)

[Claims] L: a plurality of optical scanning element arrays arranged linearly at appropriate intervals, and an imaging lens array for optically coupling each optical scanning element array to a scanning surface; A light beam deflection member disposed on at least one of the optical scanning element array side and the scanning surface side of the imaging lens array, and optical projection on the scanning surface of the plurality of optical scanning element arrays. The area or light receiving area is expanded by the imaging lens array, and the area obtained by correcting the deviation of the area in each of the optical scanning element arrays due to this expansion by the light beam deflection member is one continuous area. An optical scanning device characterized in that it is configured to form a scanning line. 2. Displacement of one piece of the optical scanning element array, a part of the imaging lens array opposite to this optical scanning element array, and the area on the scanning surface of the optical scanning element array due to this imaging lens array. The light beam deflection member for correcting the above-mentioned beam deflection member is integrally configured to form an optical scanning block, and a plurality of optical scanning blocks are arranged in correspondence to a desired scanning length. Range 1
The optical scanning device described in Section 1. & The light beam deflection member disposed on the optical scanning element array side of the imaging lens array is a convergent one, and the light beam deflection member disposed on the scanning surface side is a diverging one. An optical scanning device according to claim 1 or 2.