JPH0248868A - Fixing method for solid-state image sensor - Google Patents

Abstract

PURPOSE:To fix a solid-state image sensor onto a prescribed position with high accuracy by using an image pickup signal of the solid-state image sensor, applying fixing process and progressing fixing reaction while correcting a change till the end of fixing reaction. CONSTITUTION:An image pickup light from a test chart 31 is led to a color separation prism 1d via a master lens 32, separated into three primary colors R, G, B and irradiates on CCD image sensors 4-1 to 4-3. Each image pickup signal obtained by each sensor 4 is supplied to a matrix circuit 38 via amplifiers 36-1 to 36-3 and gate circuits 37-1 to 37-3. A picture signal obtained by the circuit 38 is fed to a monitor 42 and a microcomputer 44 via an oscilloscope 40 and a video signal processing circuit 41. Moreover, the signal is also fed to a digitizer 43, the output is inputted to a correction drive circuit 17 and converted into a drive output of a piezoelectric element provided respectively each registration adjustment mechanism 33. Then after soldering the sensor 4, the sensor is corrected and driven in a direction so that the displacement caused is made zero till the end of fixing reaction.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a solid-state image sensor using a solid-state image sensor such as a COD, which is mounted in a predetermined position of an imaging optical system with high precision. In a method of fixing an image sensor to a predetermined position of an imaging optical system, the fixing position is adjusted by a position adjustment means using the imaging signal of the solid-state image sensor to be fixed, and after the fixing operation is performed, the fixing reaction is completed. By capturing the displacement that occurs in the imaging signal as a change in the imaging signal, and proceeding with the fixation reaction while correcting the displacement using the position adjustment means or other position correction means based on this change, the solid-state image sensor can be adjusted to 100 degrees when the fixation reaction is completed.
% reliably fixed in a predetermined position with high precision.

[Prior Art] Conventionally, solid-state imaging devices such as COD have been used as image sensors in video cameras, etc., and the R, G, and B color components separated by a prism in an imaging optical system are sent to three image sensors. A color television signal is created by capturing an image. Here, it is necessary to ensure that the subject images of each color component imaged by each image sensor are maintained in a state in which they are overlaid, that is, the so-called registration registration adjustment is performed accurately. There is a need for a technique to fix the optical system to the imaging optical system with an adjustment standard, that is, a submicron error. Three COD plates in the imaging optical system
When assembling a COD block with an image sensor fixed thereon, the image sensor was fixed using the following method using a registration adjustment device.

(1) Screw fixation (2) Adhesive fixation (3) Solder fixation Of these, (1) screw fixation requires high component dimensional accuracy and sometimes causes large displacements, so it is not commonly used. The fixing methods (2) and (3) are used.

FIG. 4 is an explanatory diagram of a conventional method of fixing a solid-state image sensor, and shows the assembly of a COD block. C
The OD block includes a light emitting section 1a for each separated light in the optical block 1 that accommodates a color separation prism for the imaging light;
A holder 2 having a fixing claw 2+1 is connected to each of Ib and Ic, while a claw 3 corresponding to the claw 2a is connected to each of Ib and Ic.
Each image sensor it, 4-2 is attached to the holder 3 having a
4-3 (hereinafter referred to as 4 in a representative case), the image sensor 4 is subjected to registration adjustment in 6-axis directions using the registration adjustment mechanism described below, and then both holders 2, The claws 2a and 3a of No. 3 were fixed to each other by heat welding such as soldering, and assembly was performed.

FIG. 5 is a perspective view for explaining a conventional registration adjustment mechanism. The image sensor 4 joined to a holder (not shown) is inserted into a socket 5 of this mechanism and held, and registration adjustment is performed in the adjustment direction shown by the arrow. In other words, the adjustments are: - Horizontal center (arrow ±X direction) adjustment - Vertical center (arrow ±Y direction) adjustment - Back focus (arrow ±Z direction)
Force direction adjustment ■Horizontal tilt (arrow ±R, turning direction)
Adjustment■ Vertical tilt (arrow ±Ry rotation direction) adjustment■
This is adjustment in 6-axis directions of rotation (arrow 10 direction) adjustment. In order to make these adjustments possible, the rhenostrone adjustment mechanism includes a Z-direction adjustment mechanism 6, a Y-direction adjustment mechanism 7, an X-direction adjustment mechanism 8, a θ-direction adjustment mechanism 9,
Rx turning direction adjustment mechanism IO and Ry turning direction adjustment mechanism 1
1. Each adjustment mechanism is constructed using a micrometer, and its rotation shaft is rotated in forward and reverse directions by a predetermined amount to perform rhenostrength adjustment.

FIGS. 6(a) and 6(b) show the above-mentioned conventional cash register storage 3.
FIG. 3 is an explanatory diagram of a registration adjustment method in the tone adjustment mechanism. Registration adjustment is performed by detecting registration errors in each adjustment direction using the imaging signal of the test chart by an image sensor held in the registration adjustment mechanism, and correcting the errors by operating the corresponding adjustment mechanism part. It will be done. The test chart shows the pixel pitch τ of the image sensor. The image sensing signal of the image sensor has a pixel pitch τ. (b) due to the difference between and the repetition pitch τ2
Since the beat component shown in is generated, the registration error is detected from the zero crossing point, level, etc. of this beat component.

These measurement techniques are described in Japanese Patent Application Laid-open No. 6, which the applicant previously applied for.
This is disclosed in Japanese Patent No. 1-288683.

As described above, the conventional method for fixing an image sensor to an imaging optical system is to fix the image sensor with solder or the like after completion of the contrast adjustment.

[Problem M to be Solved by the Invention] However, in the image sensor fixing method in the above-mentioned conventional technology, regardless of the fixing method (2) adhesive fixing or (3) solder fixing, adhesive or Due to shrinkage stress or expansion of the solder, there is a problem in that the adjusted registration is displaced (misaligned) before the adhesive or solder fixation reaction is completed. For example, the adjustment standard in the X and Y directions for a three-plate COD block is 10 μm or less, and the allowable displacement amount is submicron. At present, there is no effective countermeasure to prevent the above displacement, and measures are being taken to strictly suppress the ingredients of the adhesive or solder, heating conditions, holder material, etc. that cause the displacement. It was impossible to suppress the displacement.

Therefore, if a displacement exceeding the allowable value occurs, the product becomes defective, and it is necessary to remove the adhesive or solder and perform the fixing operation again, reducing production capacity. In order to make this product 100% good from the beginning, it is possible to consider measures to increase the rigidity of the registration device, etc., but new problems arise such as the need for a large investment in equipment.

The present invention was devised to solve the above-mentioned problems, and suppresses the displacement after the fixing operation is completed until the fixing reaction is completed.
It is an object of the present invention to provide a method for fixing a solid-state image sensor that allows a solid-state image sensor to be fixed in a predetermined position with 100% certainty and high precision.

[Means for Solving the Problems] The structure of the solid-state image sensor fixing method of the present invention for achieving the above object is as follows: The position of the solid-state image sensor is determined based on the imaging signal of the test chart by the solid-state image sensor. A method for fixing a solid-state image sensor, which includes a step of adjusting with an adjusting means and performing a fixing operation, captures the displacement of the solid-state image sensor that occurs after the fixing operation and until the completion of the fixing reaction as a change in the imaging signal, and detects the change. The present invention is characterized by comprising the step of converting the drive output of the position adjusting means or other displacement correcting means and driving to correct the displacement in parallel until the fixing reaction is completed.

[Function] The present invention detects the displacement of the solid-state image sensor that occurs after the fixing operation of the solid-state image sensor is completed until the fixing reaction is completed based on the imaging signal of the solid-state image sensor, and adjusts the position of the solid-state image sensor according to the fixing agent. Alternatively, the displacement position is made as small as possible by proceeding with the fixation reaction while applying correction using the displacement correction means.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings. In the following description, members having the same functions as those of the conventional example are given the same reference numerals to simplify the description.

FIG. 1 is an exploded perspective view showing one embodiment of a registration adjustment mechanism used to implement the present invention.

This embodiment shows an example of a registration adjustment mechanism for correcting displacement until the fixation reaction is completed, particularly in the horizontal X direction and vertical Y direction of a COD image sensor that requires submicron positional accuracy. 6 is an X-direction adjustment mechanism; 12 is an X-direction adjustment mechanism fixed on the table of the X-direction adjustment mechanism 6; 13 is an X-direction adjustment mechanism fixed on the table of the X-direction adjustment mechanism 12; 9 is an X-direction adjustment mechanism A θ direction adjustment mechanism fixed on the table of the mechanism 13, IO an Rx rotation direction adjustment mechanism fixed on the table of the θ direction adjustment mechanism 9, and an Rx rotation direction adjustment mechanism 11 attached so as to be rotatable. The Ry turning direction adjustment mechanism 5 is a socket fixed to the Ry turning direction adjustment mechanism 11. 6.
Each of the adjustment mechanisms 9 to 2 and the socket 5 are the same as in the conventional example, and each of the X-direction adjustment mechanism 12 and the X-direction adjustment mechanism 13 is equipped with a micrometer and a movable table similar to the conventional example. A piezoelectric element +4 (or 15) serving as a displacement correction means is attached to the tip of the micrometer. This piezoelectric element 1415 has a function of making fine adjustments in submicron units at high speed in each adjustment direction.

The COD image sensor 4 before being fixed is inserted into the socket 5 and held, and the lens strain adjustment is performed by operating each adjustment mechanism. I6 is CCD image sensor 4
This is a displacement detection means that detects the displacement from the normal position as a change in the image signal based on the image signal of the conventional example. The detection means can be shared. Reference numeral 17 is a correction drive circuit that converts the change in the image signal into a drive output of the piezoelectric elements 14 and 15, and it starts operating after registration adjustment and after thermal welding such as soldering, and completes the solder fixation reaction. In parallel to that, the CO after adjusting for rhenostorage
It has a function of correcting and driving the displacement of the D image sensor 4.

FIG. 2 is a diagram showing an example of the configuration of the main parts of the adjustment mechanism in the Y direction (or X direction). 21 is a fixed side, 22 is a male screw fixed to the table side 23 that can slide in the Y direction (or X direction) with respect to the fixed side, and 24 is a rotating shaft of a micrometer having a male screw that is screwed into this acid screw. , 14. (
or 15) is the aforementioned piezoelectric element provided on the axis of this rotating shaft 24 and fixed to the fixed side 21, and 25 is the piezoelectric element 14 (or 1
5) is a hole provided in the contact portion that functions as a bearing. For example, the piezoelectric element 14 (or 15) receives a positive voltage (
When a voltage (driving output) is applied, it expands, and when the opposite voltage is applied, it contracts, moving the table side 23 in submicron units. The rotating shaft 24 of the micrometer is the motor 2
It is also possible to rotate by 6.

FIG. 3 is a block diagram showing an example of the configuration of the displacement detecting means, and shows an example in which the means for detecting registration error used in conventional registration adjustment is shared. A test chart 31 is composed of a repeating pattern having a repeating pitch having a predetermined relationship with the pixel pitch of the image sensor, and is arranged in front of the master lens 32 of the imaging optical system. The imaging light of the test chart 3I is passed through the master lens 32 to the color separation prism Id of the optical block of the 3 temporary COD color video camera.
The color separation prism Id separates the above-mentioned imaging light into three primary color lights R-G-B, that is, red component light R1, green component light G, and blue component light B, and separates them into three COD image sensors 4-1゜1. -2. 4-3 is irradiated.

”-9 Each image sensor 4-1.4-2.4-3 is
The aforementioned six-sleeve registration adjustment mechanism 331.3
3-2.33-3 (Hereinafter, if it is representative, it will be written as 33)
can be attached to each socket. Each image sensor 4 is driven by a COD drive circuit 35 that operates based on a reference signal provided by a reference signal generator 34.
An image, that is, a test chart, is captured using the imaging light of each color component separated by the color separation prism ld. Each image signal obtained by each of the above COD image sensors 4 is
Each preamplifier 36-1.36-2.36-3 supplies the matrix circuit 38 via each gate circuit 37-ratio 37-2.37-3.

Here, each gate circuit 37-1.37-2.37-3 for extracting a specific portion of the heat component is supplied with a gate pulse generated by a gate pulse generation circuit 39 that operates based on the reference signal. .

The image signal obtained by the matrix circuit 38 is supplied to an onroscope 40 for waveform observation, a high resolution monitor 42 via a video signal processing circuit 41, and further supplied to a microcomputer 44 via a digitizer 43. is supplied to

The digitizer 43 has a function of digitizing and outputting errors or displacements in each registration adjustment direction. In this embodiment, the output is input to the correction drive circuit 17 and converted into the drive output of the piezoelectric element provided in each registration adjustment mechanism 33 as described above. In this step, a correction drive is applied in a direction in which the displacement generated until the fixation reaction is completed becomes zero.

In the above, the input to the correction drive circuit 17 may be performed from the microcomputer 44.

A method of fixing the COD image sensor to the imaging optical system (optical block) in the embodiment configured as above and its operation will be described. First, the three CCD image sensors 4 are attached to the three rhenostrain adjustment mechanisms 33, and the imaging signal of the test chart 31 is detected on an oscilloscope using the rhenostrain error detection means that also serves as the displacement detection means shown in FIG. 40 and the high-resolution monitor 42, operate the registration adjustment mechanism 33 to eliminate the registration error, and align the four claws 2a of the holder on the optical block (prism) 1 side shown in FIG. Using the four claws 3a of the holder on the image sensor side, the four locations are simultaneously welded with solder. After this welding operation and until the fixing reaction is completed, displacement (positional shift) occurs in the once adjusted registration adjustment due to thermal expansion or contraction stress.

Therefore, in this embodiment, the amount of displacement generated between the welding operation and the completion of the adhesion reaction is adjusted to the COD image sensor 4, including the direction of displacement, as in the case of registration adjustment.
A fixing agent with a short fixing reaction time like solder is detected by using the imaging signal of the test chart 31, converts the amount of displacement, and applies correction drive using a displacement compensation means with a quick response such as a piezoelectric element. In response to this, the amount of displacement is minimized by promoting the fixation reaction.

In the above embodiment, the process was carried out in the X and Y directions, where registration displacement is particularly problematic, but it goes without saying that the process can be carried out in the same way in other directions as well. Furthermore, if the fixing agent is an adhesive, the fixing reaction is relatively slow, so instead of using a piezoelectric element, the correction drive of the micrometer's rotation axis may be driven by a motor that can control rotation by a predetermined amount in forward and reverse directions. . The motor at this time can also be used as a position adjustment means when performing the reno strain movement operation by motor drive. As described above, the present invention can be applied in various ways in accordance with its gist and can take various embodiments.

[Effects of the Invention] As is clear from the above explanation, according to the method for fixing a solid-state image sensor of the present invention, after adjusting the renostration,
To suppress the displacement that occurs during the completion of the fixing reaction of the fixing agent. The fixed image sensor can be fixed to the imaging optical system 100% reliably with a predetermined high precision.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing one embodiment of the registration adjustment mechanism used to implement the present invention, FIG. 2 is a configuration diagram of the main parts of the adjustment mechanism in the X direction or Y direction, and FIG. 3 is a displacement detection means. FIG. 4 is an explanatory diagram of a conventional fixing method for a solid-state image sensor, FIG. 5 is a perspective view of a conventional registration lane adjustment mechanism, and FIG.
L) and (b) are explanatory diagrams of a conventional registration adjustment method. 4...Image sensor, I2...X direction adjustment mechanism, 13
...Y direction adjustment mechanism, 14.15...Piezoelectric element, 1
6... Displacement detection means, 17... Correction drive circuit.

Claims (1)

[Claims] (1) In a method for fixing a solid-state image sensor, which includes a step of adjusting the position of the solid-state image sensor using a position adjustment means and performing a fixing operation based on an imaging signal of a test chart by the solid-state image sensor, the fixing reaction is completed after the fixing operation. The displacement of the solid-state image sensor that occurs up to that point is captured as a change in the imaging signal, and the change is converted into a drive output of the position adjustment means or other displacement correction means, and the change is changed in parallel to the displacement until the fixation reaction is completed. A method for fixing a solid-state image sensor, comprising a step of correcting driving.