JP2003259384A - Solid-state imaging unit and method for assembling solid- state imaging unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid-state imaging unit in which six axial adjustment is possible and a CCD and a color separation prism are closely adhered. <P>SOLUTION: A convex glass plate 3a and a concave glass plate 3b are placed between the CCD1 and the color separation prism 2, an adhesive is coated and the adhered face is closely held. While the closely adhered state is maintained, a relative position between the convex glass plate 3a and the concave glass plate 3b is changed to change the position of the CCD1 with respect to the color separation prism 2 for adjusting a light receiving plane so as to be perpendicular to the optical axis. Further, the 6 axes are adjusted in addition to the movement of the CCD itself and the adhesive is cured. The six axes can be adjusted without intervention of an air layer, no reflection prevention film is required and undesirable reflected lights can be decreased to attain the assembling with high accuracy. As a result, the inexpensive solid-state imaging unit with less number of components and high image quality and the assembling method for the solid-state imaging unit are provided. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state image pickup device in a television camera or the like having a solid-state image pickup element (hereinafter, CCD will be described as a typical example) and a method for assembling the solid-state image pickup device.

[0002]

2. Description of the Related Art At present, most broadcasting / commercial cameras such as television cameras use a color separation prism to separate light into three primary colors of red, green, and blue, and to form an image on each CCD. Has been adopted. In such a spectroscopic optical system, three CCDs are arranged along the six axes (X, Y,
Z, θx, θy, θz) with high accuracy,
It is necessary to bond and fix it to the color separation prism. As a conventional solid-state imaging device and a method for assembling the solid-state imaging device, the one described in Japanese Patent Laid-Open No. 4-290090 is known.

A conventional method for assembling a solid-state image pickup device will be described below with reference to FIG. FIG. 5 is an overall view of a conventional solid-state imaging device.

As shown in FIG. 5, the conventional solid-state image pickup device is composed of CCDs 111, 112, 113 and color separation prisms 121, 122, 123.

Color separation prisms 121, 122,
An adhesive agent is sandwiched between the bonding surfaces of 123 and they are closely attached. Since the whole is held in a temporarily assembled state, the color separation prism 122 is indicated by an arrow a in FIG.
The color separation prism 123 is movable along the cemented surface in the direction of arrow b. An ultraviolet curing type is used as the adhesive. C
The CDs 111, 112, 113 are in close contact with the emission surfaces of the color separation prisms 121, 122, 123, respectively, with an adhesive interposed therebetween, and are held in a temporarily fixed state. CCD 111, 11
Reference numerals 2 and 113 are movable in the directions of arrows X and Y in the drawing, and rotatable in the direction of θz in the drawing.

Next, in this state, the CCDs 111, 112,
The test chart is imaged with 113 as the imaging state. First, after monitoring the image pickup signals of the CCDs 111 and 112 and focusing the image pickup lens on the CCD 111, CC
Color separation prism 1 so that the image formation state of D112 is the best
22 is moved along the joint surface to adjust the optical path length in the Z direction (optical axis direction). Similarly, the color separation prism 12 is monitored so that the image pickup signal of the CCD 113 is monitored and the image formation state is optimized.
3 is moved along the joint surface to adjust the optical path length in the Z direction.

Next, X, along the emission surface, so that the pixel position of the CCD 111 becomes a predetermined position with respect to the test chart.
The position is adjusted by moving in the Y and θz directions. CCD 11
The pixels 2 and 113 are also moved in the X, Y, and θz directions along the emission surface so that the pixels are aligned so that they have a predetermined positional relationship with the test chart.

In this state, ultraviolet rays are irradiated to cure the adhesive on each joint surface.

In such a conventional assembling method, it is possible to adjust the four axes X, Y, Z and θz of the six-axis adjustment, but it is impossible to adjust θx and θy. The emission surfaces of the color separation prisms 121, 122, and 123 are designed to be flat surfaces with the optical axis as a normal line. A deviation between the line and the optical axis is inevitable. Further, the parallelism between the front glass of the CCDs 111, 112 and 113 and the imaging plane also deviates for the same reason. Therefore, according to the conventional assembling method in which the adjustments of θx and θy are impossible, the CCDs 111 and 11 are highly accurate with respect to the optical axis.
2 and 113 could not be adhered to the color separation prisms 121, 122 and 123, and as a result defocus and color shift occurred and high image quality could not be obtained.

On the other hand, the color separation prisms 121, 1
There is a conventional example in which an air layer is interposed between the CCDs 22, 123 and the CCDs 111, 112, 113 so that the six axes can be adjusted, but a reflection interface between glass and air is generated, and unnecessary reflections impair the image quality. There were challenges. In addition, there is a problem in that it is necessary to form an antireflection film on the reflecting surface, and the cost is high. Further, in order to interpose an air layer, the color separation prisms 121, 122, 123 and the CCDs 111, 112,
A member for connecting with 113 is required, and conventionally four members such as wedge-shaped glass, a connecting metal plate, and a ceramic for holding and holding are used as these members, and there is a problem that the number of parts is large and the cost is high. Further, when the light is shielded after the assembly, there is a problem that a dedicated light shield member has to be provided and the number of parts is large.

[0011]

As described above, the conventional solid-state image pickup device and the conventional method for assembling the solid-state image pickup device cannot perform 6-axis adjustment. Therefore, the CCD can be used as a color separation prism with high accuracy with respect to the optical axis. There is a problem that they cannot be adhered, and as a result, a focus shift or a color shift occurs and a high image quality cannot be obtained.

Further, in the conventional example in which 6 axes can be adjusted,
There is a problem that a reflection interface between glass and air is generated and unnecessary reflection impairs image quality. In addition, it is not only necessary to form an antireflection film on the reflecting surface, but also a connecting member between the color separation prism and the CCD is required, which causes a problem of high cost.

The present invention has been made to solve the above-mentioned problems, and enables six-axis adjustment without interposing an air layer between the color separation prism and the CCD, and the number of parts is small and the cost is high. An object of the present invention is to provide a solid-state imaging device having high image quality and a method for assembling the solid-state imaging device.

[0014]

In order to solve this problem, the present invention comprises a solid-state image sensor, a color separation prism, a transparent member having a convex curved surface, and a transparent member having a concave curved surface. The member and the concave transparent member have an area sufficient to include the effective image pickup area of the solid-state image pickup device, and the curvature R1 of the convex transparent member and the curvature R2 of the concave transparent member are substantially the same, and the curved surfaces are matched. Is integrally inserted between the color separation prism and the solid-state image sensor, and is closely adhered and fixed in the effective light ray range without an air layer.

According to the present invention having such characteristics,
It is possible to obtain a solid-state imaging device that has a small number of parts and is inexpensive and has high image quality.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention comprises a solid-state image pickup element, a color separation prism, a transparent member having a convex curved surface, and a transparent member having a concave curved surface, and the convex transparent member. And the concave transparent member have an area sufficient to include the effective image pickup area of the solid-state image sensor, and the curvature R1 of the convex transparent member and the curvature R2 of the concave transparent member are substantially the same.
A curved interface is integrated and inserted between the color separation prism and the solid-state image sensor, and is closely adhered and fixed in the effective ray range without an air layer interposed. A reflective interface formed between glass and air. This has the effect of reducing unnecessary reflected light.

According to the second aspect of the present invention, the curved surfaces of the convex transparent member and the concave transparent member are spherical surfaces, and there is no reflective interface between glass and air, and unnecessary reflected light can be reduced. Have.

According to a third aspect of the present invention, the curved surfaces of the convex transparent member and the concave transparent member are slid to adjust the perpendicularity between the optical axis and the light receiving plane of the solid-state image sensor. Axis and C
This has the effect that the perpendicularity to the CD light receiving surface can be adjusted with high accuracy.

According to a fourth aspect of the present invention, there is provided a solid-state image pickup device, a color separation prism, and a connecting member having a concave curved surface, and the connecting member is a through window sufficient to include an effective image pickup area of the solid-state image pickup device. In addition, it is inserted between the color separation prism and the solid-state image sensor to adjust the verticality between the optical axis and the light-receiving plane of the solid-state image sensor. It has the effect that it can be adjusted well.

FIG. 1 shows an embodiment of the present invention.
4 to FIG.

(Embodiment 1) FIG. 1 is an overall view of a solid-state image pickup device according to an embodiment of the present invention, and FIGS. 2 and 3 are partial views thereof.

As shown in FIG. 1, the solid-state image pickup device of the present invention includes CCDs 1R, 1G and 1B as solid-state image pickup elements, and
The color separation prism 2, the convex glass 3a as a transparent member having a convex curved surface, and the concave glass 3b as a transparent member having a concave curved surface.

As shown in FIG. 2, the convex glass 3a and the concave glass 3b form a convex curved surface 3ar and a concave curved surface 3br, respectively. The curved surfaces 3ar and 3br are spherical surfaces having the same curvature, and when the curved surfaces are matched with each other as shown in FIGS. 1 and 3, no gap is generated. The color separation prism 2 is composed of a red block 2R, a green block 2G and a blue block 2B. The color separation prism 2 separates the light flux from the imaging lens into different wavelengths with a dichroic film,
The emitting surface 2Ra has a function of emitting a red (R) wavelength band, the emitting surface 2Ga of a green (G) wavelength band, and the emitting surface 2Ba of a blue (B) wavelength band. The inclinations of the emission surfaces 2Ra, 2Ga, 2Ba of the color separation prism 2 are RG, respectively.
It is configured to be a plane whose normal is the optical axis of each B channel. Each emission surface 2Ra, 2G of the color separation prism 2
a and 2Ba, the flat surface portion of the concave glass 3b is tightly joined, and further, the CCDs 1R, 1G, and 1B are tightly joined to the flat portion of the convex glass 3a, and the color separation prism 2 and the CCD 1R, 1
The convex glass 3a and the concave glass 3b are sandwiched between G and 1B and held.

An ultraviolet-curing adhesive is applied to all the joint surfaces, and the emission surfaces 2Ra and 2G of the color separation prism 2 are applied.
The paths from a, 2Ba to the CCDs 1R, 1G, 1B are closely joined without an air layer. At this time, the CCDs 1R, 1G and 1B are lightly pressed in the direction of pressing the convex glass 3a in the optical axis direction. In this state, since the adhesive is uncured, each joint surface can be moved and rotated in the plane.

Next, the CCD 1R, 1G and 1B are positioned with high accuracy while monitoring the image pickup signals of the CCDs 1R, 1G and 1B which have picked up the CCD positioning adjustment chart. In order to obtain a color separation optical system with high image quality without color shift or focus shift, it is important to fix the light receiving planes of the CCDs 1R, 1G, 1B accurately with respect to the optical axis. Therefore, 6-axis adjustment is performed for all CCDs 1R, 1G, and 1B. That is, as shown in FIG. 3, the optical path length direction Z,
6-axis adjustment of registration directions X and Y, rotation θz about the optical axis, and tilts θx and θy of the light receiving plane.

Hereinafter, the color separation prism 2 and the CCD 1R, 1
A method of adjusting the six axes without interposing an air layer between G and 1B will be described. In the optical path length direction Z, each block 2R, 2G, 2B of the color separation prism 2 is moved along the joint surface as in the conventional technique.

The tilts θx and θy of the light receiving plane can be obtained by sliding the curved surfaces of the convex glass 3a and the concave glass 3b. That is, with the color separation prism 2 and the concave glass 3b fixed, the convex glass 3a and the CCD 1
And rotate together. At this time, since the curved surfaces of the convex glass 3a and the concave glass 3b are spherical surfaces having the same curvature,
It is possible to adjust the tilts θx and θy of the light receiving plane without interposing an air layer in the close contact joint.

CC in the X, Y and θz directions
The D itself is moved and rotated within the joining plane with the convex glass 3a for adjustment. When the adjustment is completed for all 6 axes,
Ultraviolet rays are irradiated to cure the adhesive on each joint surface.

In this way, it is possible to adjust all six axes without interposing an air layer between the color separation prism 2 and the CCD 1. The above is R, G, B
However, by finally adjusting all channels, an image pickup device with high image quality can be obtained.

Further, when the light is to be shielded after the assembling, the convex glass 3a, the concave glass 3b and their surroundings only have to be painted black, and it is not necessary to provide a new light shielding member.

The above procedure is an example, and the present invention is not limited to this and can be arbitrarily changed. For example,
Adjusting the X, Y, and θz directions to tilt the light-receiving plane θx and θ
The order of adjusting y and adjusting the optical path length Z may be used.

In the above description, the color separation prisms 2 and C
Although the convex glass 3a and the concave glass 3b are inserted between the CD1 and the CD1, it can be similarly implemented between other optical filters and other optical light receiving elements. A color filter array may be used instead of the color separation prism 2.

(Second Embodiment) FIG. 4 is an overall view of a solid-state image pickup device according to an embodiment of the present invention.

As shown in FIG. 4, the solid-state image pickup device of the present invention comprises a CCD 1 as a solid-state image pickup element, a color separation prism 2, and a ceramic 4 as a connecting member provided with a through window in the optical axis direction. To do. The through window of the ceramic 4 has a size that does not block the effective light flux that reaches the CCD 1 from the color separation prism 2. The ceramic 4 has a concave curved surface 4r.
Make up.

The flat surface of the ceramic 4 is closely bonded to the emission surface of the color separation prism 2, and the CCD 1 is bonded to and held by the concave curved surface 4r of the ceramic 4. At this time, the corners 1a of the four corners of the CCD 1 and the concave curved surface 4r of the ceramic 4 are joined. An ultraviolet curable adhesive is applied to all joint surfaces.

In this state, as in the first embodiment, the CCD
Adjust the 6-axis position of 1. Regarding the optical path length direction Z, each block 2R of the color separation prism 2,
2G and 2B are moved along the joint surface.

Next, regarding the tilts θx and θy of the light receiving plane, the corners 1a of the CCD 1 and the concave curved surface 4 of the ceramic 4 are used.
Adjustment is performed by changing the relative position of each other so as not to separate from r. That is, since the movement locus of the corner 1a of the CCD 1 is the curved surface 4r, the tilt adjustment can be performed.

The X, Y, and θz directions are adjusted by moving and rotating in the joint plane between the color separation prism 2 and the ceramic 4. When the adjustment is completed for all six axes, ultraviolet rays are irradiated to cure the adhesive on each joint surface.

In this way, the color separation prism 2 and the CCD 1 can be adjusted for all six axes.

The above procedure is an example, and the present invention is not limited to this and can be arbitrarily changed. For example,
Adjusting the X, Y, and θz directions to tilt the light-receiving plane θx and θ
The order of adjusting y and adjusting the optical path length Z may be used.

[0041]

As described above, according to the present invention, since the air layer is not interposed between the color separation prism and the CCD, the antireflection film is not necessary and unnecessary reflected light is not generated. The advantageous effect of reduction can be obtained. At the same time, the 6-axis adjustment is possible, so that there is an advantageous effect that the assembly can be performed with high accuracy. Further, since they are closely joined, the advantageous effect that the dustproof property after assembly is good can be obtained.

Further, since only the convex glass and the concave glass are arranged between the color separation prism and the CCD, the number of parts is small and the cost is low.

Since only the ceramic is arranged between the color separation prism and the CCD, the number of parts is small and the cost is low.

[Brief description of drawings]

FIG. 1 is an overall view of a solid-state imaging device according to an embodiment of the present invention.

FIG. 2 is a partial view of a solid-state imaging device according to an embodiment of the present invention.

FIG. 3 is a partial view of a solid-state imaging device according to an embodiment of the present invention.

FIG. 4 is an overall view of a solid-state imaging device according to an embodiment of the present invention.

FIG. 5 is an overall view of a conventional solid-state imaging device

[Explanation of symbols]

1 CCD Two-color separation prism 3a Convex glass 3b concave glass 4 ceramic

Claims (4)

[Claims] 1. A solid-state imaging device, a color separation prism, a transparent member having a convex curved surface, and a transparent member having a concave curved surface, wherein the convex transparent member and the concave transparent member are effective for the solid-state imaging device. The convex transparent member has a curvature R1 and the concave transparent member have a curvature R2 that are substantially equal to each other while having an area sufficient to include an imaging region, and the curved surfaces are integrated to integrally form the color separation prism and the color separation prism. A solid-state image pickup device characterized by being inserted between a solid-state image pickup device and closely adhered and fixed without an air layer in the effective ray range. 2. The solid-state imaging device according to claim 1, wherein the curved surfaces of the convex transparent member and the concave transparent member are spherical surfaces. 3. The perpendicularity between the optical axis and the light receiving plane of the solid-state imaging device is adjusted by sliding the curved surfaces of the convex transparent member and the concave transparent member. Assembling method of the solid-state imaging device. 4. A solid-state imaging device, a color separation prism, and a connecting member having a concave curved surface, wherein the connecting member has a through window sufficient to include an effective imaging area of the solid-state imaging device, and A solid-state imaging device, which is inserted between a color separation prism and the solid-state imaging device to adjust the verticality between an optical axis and a light-receiving plane of the solid-state imaging device.