JP2016025602A - Imaging apparatus and processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging apparatus that can be attached to a fine manipulator or the like without damaging its operability and is capable of imaging a target properly, and to provide a processing apparatus provided with the imaging apparatus.SOLUTION: An imaging apparatus 1 comprising a solid state imaging device 2 comprising a two-dimentional array of pixels 3 each comprising a photoelectric converter 13 for generating a signal charge by photoelectric conversion of incident light is provided with a via hole 4 through nearly the center of the imaging apparatus from the front face to the rear face.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an imaging device having a solid-state imaging device and a processing apparatus including the imaging device.

  Conventionally, for example, a micromanipulator has been used for assembling a minute part such as an electronic part or processing a minute object (for example, see Patent Document 1). Examples of the micromanipulator include those having a laser cutter or a laser marker for processing a minute object at the tip, and vacuum tweezers equipped with a suction nozzle for sucking an electronic component such as a minute capacitor at the tip. These micromanipulators are attached to a drive mechanism or the like that can be moved in three XYZ directions in order to automatically perform processing on an object such as a minute component or minute object.

  For example, when using a vacuum tweezers to move and assemble a micro capacitor placed on a parts rack, the micro capacitor is first sucked and adsorbed by vacuum tweezers. Next, the vacuum tweezers are moved by the drive mechanism so that the minute capacitor comes directly above the semi-finished product placed on the assembly rack. Then, the position and posture of the vacuum tweezers are adjusted so that the position and posture of the minute capacitor become the target position and posture, the vacuum tweezers are lowered, and the minute capacitor is installed at the target position.

  Usually, when such an operation is performed, a video camera or the like is used for measurement for positioning. For example, a mesh consisting of black lines perpendicular to each other is provided on the surface of a transparent parts rack, and a video camera captures the microparts such as microcapacitors and the tip of vacuum tweezers from below, and the resulting image contains a mesh Are also captured at the same time, it is possible to accurately measure the position and orientation of the tip of the vacuum tweezers and the relative positional relationship between the vacuum tweezers and the minute parts by image processing.

  On the other hand, since the semi-finished product on the assembly rack is opaque, acquisition of an image for positioning by image processing is performed by a plurality of cameras arranged obliquely above. For this reason, the accuracy at the time of installation is lower than that at the time of taking out the minute parts from the parts rack. Such an effect increases as the size of the component decreases.

  As described above, various techniques, such as sampling of a sample under a microscope, are necessary in addition to assembling the above-mentioned micro parts, while monitoring the attitude of a minute object with a camera and making it a manipulator. There is. In addition, a technique for performing positioning and posture control with high accuracy by image processing is also useful when processing or measuring a fine object. With such a technique, for example, fine processing of jewelry, very local temperature measurement, and the like can be performed more efficiently with higher accuracy. In particular, it is an indispensable technique when some of these processes are performed with the aid of robot technology, or in the case of a remote fine process in a vacuum or harmful gas.

  On the other hand, as an image sensor, there is a functional image sensor in which a functional circuit is incorporated in a pixel unit or a pixel group unit as an example of a highly functional technique (see, for example, Patent Document 2). In particular, a three-dimensional junction element in which an imaging element chip and an image information processing chip are formed on different chips and bonded and integrated can be enhanced in function without increasing the area of the imaging element. In addition, high-performance elements in which various types of optical filters, scintillators, microlenses, and the like are provided on the image sensor in units of pixels or pixel groups have been developed.

  In addition, a compound eye camera in which a large number of lenses are mounted on the light receiving surface of an image sensor has been developed (see, for example, Patent Document 3). In a compound eye camera, a group of one lens and a plurality of pixels below it becomes one element camera, and a single image is created by performing image processing on a large number of images obtained from a large number of element cameras. Can do. An optical system in which one lens is mounted on one image sensor has a higher resolving power. However, in a compound eye camera, an image sensor having a small pixel size is used, and the lens is used as a microlens to form the optical system and the image sensor. By integrating the, the camera can be made extremely compact. Moreover, distance measurement etc. can also be performed simultaneously by changing the kind of lens or optical filter. Patent Document 3 discloses an example in which element cameras are arranged on a curved surface, and a curved compound eye camera can also be made by using a flexible IC material.

  As an image sensor, a back-illuminated image sensor is known in which light is incident from the back surface opposite to the surface on which the chip electrodes and the like are arranged (see, for example, Patent Document 4). In this backside illuminating type imaging device, the photoelectric conversion element of each pixel is provided on the back side of the chip, and a circuit for performing some processing on signal charges such as an A / D converter and a signal storage unit is provided on the front side of the chip. Therefore, light can be efficiently incident and sensitivity can be improved.

JP 2004-205366 A JP 2012-191246 A Patent No. 4012752 JP 09-331052 A

  In an apparatus that performs processing on a minute part or the like with a manipulator as in Patent Document 1, it is required to perform positioning and posture control with high accuracy. In order to improve the measurement accuracy of the position and posture, It is desirable to install the camera as close as possible to the tip of the manipulator.

  However, in this case, when shooting an object such as a minute part, the manipulator may be in the way and the shooting range of the camera may be limited. Further, when the camera is attached to the manipulator, the camera becomes an obstacle, the movable range of the manipulator is limited, and the mass is increased, so that there is a possibility that the manipulator's motion performance is lowered.

  Therefore, it is conceivable to attach a plurality of small cameras around the manipulator. However, when a plurality of cameras are attached to the manipulator, the apparatus becomes complicated and the operability is significantly reduced. In order to reduce the size of each camera, it may be possible to attach a plurality of compound-eye cameras each having a lens and an image sensor integrated around the manipulator. However, since the conventional normal image sensor chip is rectangular, in order to eliminate blind spots as much as possible, it is necessary to arrange four image sensors around the manipulator, which increases the number of wires of the image sensor. There is a possibility that the operability of the manipulator may be significantly impaired. In the case of a small manipulator, it is technically difficult to arrange a large number of wires around the manipulator. In addition, depending on the cross-sectional shape of the manipulator, a plurality of image sensors may not be appropriately arranged around.

  The present invention has been made in view of the above-described problems, and can be attached to a fine manipulator or the like without impairing operability, and an imaging apparatus capable of appropriately imaging an object and the imaging apparatus It is an object of the present invention to provide a processing apparatus including an imaging device.

  In order to achieve the above object, the imaging apparatus according to claim 1 is a solid-state imaging in which a plurality of pixels in which photoelectric conversion elements that generate signal charges by photoelectrically converting incident light are arranged are two-dimensionally arranged. An imaging apparatus having an element, wherein a through-hole penetrating from the front surface to the back surface is provided in a substantially central portion of the imaging apparatus.

  The imaging device according to claim 2 is characterized in that the solid-state imaging device includes a plurality of microlenses that collect incident light on the plurality of pixels.

  The imaging apparatus according to claim 3 includes a pair of solid-state imaging elements in which a plurality of pixels in which photoelectric conversion elements that generate signal charges by photoelectrically converting incident light are arranged are two-dimensionally arranged. The pair of solid-state imaging devices are each provided with a recess, and the through-hole is formed by arranging the pair of solid-state imaging devices so that the respective recesses face each other. And

  The imaging apparatus according to claim 4 is characterized in that the solid-state imaging device includes a light emitting element.

  The imaging apparatus according to claim 5 is characterized in that the solid-state imaging device is a back-illuminated solid-state imaging device.

  A processing device according to a sixth aspect is a processing device including the imaging device according to any one of the first to fifth aspects, wherein the processing means for processing an object passes through the through hole. An imaging device is arranged. Here, the processing means includes not only an object such as a manipulator for processing an object but also a gas or a fluid such as a laser or air for performing some processing on the object.

  According to the imaging apparatus of claim 1, an imaging apparatus having a solid-state imaging element in which a plurality of pixels in which photoelectric conversion elements that generate signal charges by photoelectrically converting incident light are arranged are two-dimensionally arranged. Since there is a through-hole penetrating from the front surface to the back surface in the substantially central part, a fine manipulator etc. can be inserted and attached to this through-hole, suppressing the increase in the number of wires and mass, and operation It can prevent that property is impaired. Moreover, by inserting a fine manipulator or the like through the through hole and attaching it, it is possible to suppress the generation of a blind spot, and it is possible to appropriately image the object.

  According to the imaging device of the second aspect, since a plurality of microlenses that collect incident light with respect to a plurality of pixels are provided, it is possible to reduce the size while collecting incident light, and to operate more easily. It can be appropriately attached to a minute manipulator or the like without impairing the performance.

  According to the imaging device of claim 3, the pair of solid-state imaging elements in which a plurality of pixels in which photoelectric conversion elements that photoelectrically convert incident light to generate signal charges are arranged two-dimensionally are Since a through hole is formed by arranging a pair of solid-state imaging devices so that the respective concave portions are opposed to each other, attach a fine manipulator or the like to the through hole. It is possible to prevent the number of wires from increasing and the mass from increasing, and to prevent the operability from being impaired. Moreover, by inserting a fine manipulator or the like through the through hole and attaching it, it is possible to suppress the generation of a blind spot, and it is possible to appropriately image the object.

  According to the imaging device of the fourth aspect, since the solid-state imaging device includes the light emitting element, it is possible to capture an image of a target object appropriately without providing a light source outside. Therefore, it can be effectively attached to a fine manipulator or the like where it is difficult to provide a light source outside.

  According to the imaging device of the fifth aspect, since the solid-state imaging device is a back-illuminated solid-state imaging device, light can be efficiently incident and sensitivity can be improved.

  According to the processing apparatus of the sixth aspect, since the imaging device is arranged so that the processing means for processing the object passes through the through-hole, the object can be appropriately imaged and obtained. The object can be processed with high accuracy using the obtained image.

It is a schematic block diagram which shows an example of the solid-state image sensor which the imaging device which concerns on embodiment of this invention has. It is a schematic longitudinal cross-sectional view for demonstrating an example of the micro lens provided with respect to a some pixel. It is a schematic circuit block diagram which shows an example of the pixel of a solid-state image sensor. It is a schematic block diagram which shows another example of the solid-state image sensor which the imaging device which concerns on embodiment of this invention has. It is a schematic block diagram which shows another example of the solid-state image sensor which the imaging device which concerns on embodiment of this invention has. It is a schematic block diagram which shows an example of a pair of solid-state image sensor which the imaging device which concerns on embodiment of this invention has. It is a schematic perspective view which shows an example of the manipulator of the processing apparatus provided with the imaging device which concerns on embodiment of this invention. It is a schematic plan view which shows another example of the manipulator of the processing apparatus provided with the imaging device which concerns on embodiment of this invention.

  Hereinafter, embodiments of an imaging apparatus according to the present invention will be described with reference to the drawings. As shown in FIG. 1, an imaging device 1 according to the present invention includes a solid-state imaging device 2 in which a plurality of pixels 3 are two-dimensionally arranged in a row direction and a column direction on a semiconductor substrate. A through hole 4 penetrating from the front surface to the back surface is provided. In the present embodiment, the solid-state imaging device 2 is a so-called CMOS type solid-state imaging device 2, but may be another solid-state imaging device such as a CCD type. In FIG. 1, for convenience of explanation, the solid-state imaging device 2 includes pixels 3 arranged in a two-dimensional matrix of 8 rows × 8 columns, and a square through-hole 4 for 4 pixels in the center. However, the number of the pixels 3 is not limited to a specific number, and a plurality of pixels 3 are arranged according to the required resolution. Further, in FIG. 1, for convenience of explanation, an optical system such as a microlens 10 to be described later and some wirings are omitted.

  As shown in FIG. 1, the solid-state imaging device 2 includes a plurality of pixels 3 arranged in a two-dimensional manner, row selection circuits 5 (5a to 5d), signal storage circuits 6 (6a to 6d), and column selection circuits 7 ( 7a to 7d), an output amplifier 11, an output circuit 12, and the like. Further, as shown in FIG. 2, the solid-state imaging device 2 includes a plurality of microlenses 10 corresponding to the plurality of pixels 3. The microlens 10 is arranged on the light incident side, and is configured so that light incident on the microlens 10 is condensed on the plurality of pixels 3. In order to prevent light incident on the microlens 10 from leaking into the other pixels 3, a partition may be provided for each of the plurality of pixels 3 corresponding to each microlens 10.

  As shown in FIG. 3, each pixel 3 includes a photodiode (photoelectric conversion element) 13, a reset transistor 14, an amplification transistor 15, a selection transistor 16, and the like. The photodiode 13 generates signal charges by photoelectric conversion according to the amount of incident light, and accumulates the generated signal charges.

  The reset transistor 14 is for initializing the signal charge of the photodiode 13, and has a gate commonly connected to a reset line 17 that supplies a reset signal for each row, a source connected to the photodiode 13, The drain is connected to the power supply line 18 that supplies the power supply voltage VDD. Therefore, in the reset transistor 14, the reset signal as a control signal is supplied to the gate via the reset line 17, whereby the voltage of the photodiode 13 is reset and the signal charge is initialized.

  The amplification transistor 15 is for amplifying the signal charge stored in the photodiode 13, and has a gate connected to the photodiode 13, a source connected to the drain of the selection transistor 16, and a drain connected to the power supply line 18. It is connected. Accordingly, the on state of the amplification transistor 15 changes according to the amount of signal charge accumulated in the photodiode 13.

  The selection transistor 16 is for outputting the signal amplified by the amplification transistor 15, and is connected to the row selection line 8 provided for each row and the source is a vertical signal line provided for each column. 9 is connected. Therefore, in the selection transistor 16, the selection transistor 16 is turned on by supplying a selection signal, which is a control signal, to the gate via the row selection line 8. As a result, the signal amplified by the amplification transistor 15 is output to the vertical signal line 9 via the selection transistor 16.

  In the solid-state imaging device 2 according to the present embodiment, as shown in FIG. 1, four row selection circuits 5 (5a to 5d) are provided so as to correspond to the four pixel units 20a to 20d obtained by dividing the pixel region vertically and horizontally at the center. Four signal storage circuits 6 (6a to 6d) and a column selection circuit 7 (7a to 7d) are provided.

  Each row selection circuit 5 has a row selection line 8 connected to each row, has a timing control unit, and the like, and has a function of controlling operations of the row selection circuit 5 and the column selection circuit 6 (not shown). Based on an instruction from the control circuit, a selection signal is sequentially output to the row selection line 8. As a result, in the solid-state imaging device 2, the row selection circuit 5 reads the accumulated charges from the pixels 3 in units of rows.

  The signal storage circuit 6 is connected to each vertical signal line 9 and temporarily stores a signal output from the pixel 3 selected by the row selection circuit 5 via the vertical signal line 9. The column selection circuit 7 includes a multiplexer and the like, and sequentially outputs the electrical signals stored in the signal storage circuit 6 to the output circuit 12 via the output amplifier 11 in units of columns. The output circuit 12 includes an A / D conversion unit and the like, and sequentially outputs the electrical signal from the signal storage circuit 6 to the image processing unit 19 as an image signal. The image processing unit 19 performs image processing on the obtained pixel signal based on a predetermined algorithm to form image data. In the solid-state imaging device 2, when the row selection circuit 5 completes the readout processing for one row as described above, the next row is selected, and the above processing is repeated. Then, the output of the image data is completed by completing the processing of all the rows in all the four pixel units 20a to 20d. Note that the image processing unit 19 may be configured to be on-chip.

  In the imaging device 1 according to the present invention, the through hole 4 is formed in the center, and the pixel 3 does not exist in the center of the solid-state imaging device 2. Therefore, for example, when each pixel 3 of the pixel unit 20c located on the lower left side in FIG. 1 is read, when the row selection line 8a is selected by the row selection circuit 5c, the vertical signal line 9a portion includes Since the through-hole 4 is provided and the pixel 3 is not present, the signal cannot be read out via the vertical signal line 9a (is read vacantly), but the portion where this signal is not output (the portion where the pixel 3 does not exist) ) Is known, and the order in which the signals are output is also known, so that the image data can be obtained by reconstructing the final signal by the image processing unit 19. Note that the circuit configuration and the like provided in the solid-state imaging device 2 shown in FIG. 1 is an example, and may be changed as appropriate.

  Further, the size of the through hole 4 is not particularly limited, and is appropriately set according to an object to be inserted through the through hole 4, but at least larger than the pixel size. As a method of forming the through hole 4, for example, the pixel 3 is arranged in a two-dimensional manner on a substrate other than the part where the through hole 4 is formed. The substrate may be removed by etching or the like. In addition, the formation method of the through-hole 4 is not limited to this, You may form by cut | disconnecting a center part with a laser etc.

  Further, the solid-state imaging device 2 may be configured as a backside illumination type imaging device in which the photodiode 13 of each pixel 3 is provided on the backside of a chip that does not have various circuits, and light is incident from the backside. . When the solid-state image sensor 2 is a back-illuminated image sensor, the thickness can be reduced to about several tens of μm, so that the through hole 4 can be easily formed.

  Further, the shape of the solid-state imaging device 2 is not limited to a substantially square shape as shown in FIG. 1. For example, as shown in FIGS. 4 and 5, a polygonal shape (a substantially octagonal shape in FIG. 4). The solid-state imaging device 2a or the circular solid-state imaging device 2b may be used. As shown in FIG. 4, in the case of the substantially octagonal solid-state imaging device 2a, there is no pixel outside the hatched pixel 3a corresponding to the hypotenuse of the octagon. Is not read (i.e., is read idle), but since the order in which the signals are output is known, image data can be obtained by reconstructing the final signal by the image processing unit 19. In FIG. 4, peripheral circuits are omitted for convenience of explanation.

  Further, as shown in FIG. 5, in the case of a substantially circular solid-state imaging device 2b in which a plurality of track-like pixel regions in which a plurality of substantially fan-shaped pixels 3b are arrayed in the circumferential direction are concentrically arranged. For example, a substantially circular row selection circuit 5e is provided inside the innermost track-like pixel region, and a substantially circular column selection circuit 7e is provided outside the outermost track-like pixel region. . In FIG. 5, other circuits and the like are omitted. In the row selection circuit 5e, a row selection line 8e shared by a plurality of pixels 3b arranged in a circle is connected to each track. In the column selection circuit 7e, vertical signal lines 9e shared by the plurality of pixels 3b arranged in the radial direction are connected to each pixel region adjacent in the circumferential direction. In such a solid-state imaging device 2b, a selection signal is sequentially output to the row selection line 8e based on an instruction from a control circuit (not shown). Thereby, in the solid-state imaging device 2b, the row selection circuit 5e reads out the accumulated charges from the pixels 3b in units of tracks. Further, the shape of the through-hole 4 formed in the center of the solid-state imaging device 2 is not particularly limited, and may be set as appropriate according to the shape of the object inserted through the through-hole 4. As shown in FIG. 4, a circular or polygonal through hole 4 may be formed in the center of the solid-state imaging device 2b.

  Further, as shown in FIG. 5, the light emitting element 21 may be provided on the substrate of the solid-state imaging element 2b. As the light emitting element 21, for example, an LED (Light Emitting Diode) or the like can be used. The solid-state imaging device 2 may be configured as a functional imaging device by providing various conventionally known functional circuits in units of three pixels or a plurality of pixels. Moreover, you may make it comprise in a curved surface shape by mounting the solid-state image sensor 2 on the flexible substrate which has flexibility.

  In the imaging apparatus 1 according to the present embodiment, an example having one solid-state imaging device 2 is shown as shown in FIGS. 1, 4, and 5. However, as shown in FIG. You may comprise so that it may have a pair of solid-state image sensor 2c. As shown in FIG. 6, the pair of solid-state imaging devices 2 c are each formed in a substantially L shape, and are arranged and joined so that the recesses 22 face each other, thereby as shown in FIG. 1. An imaging apparatus in which the overall shape is substantially square and the substantially square through hole 4 is provided in the center can be configured. In FIG. 6, in order to explain the shape of each of the pair of solid-state imaging devices 2c, a gap is provided between the pair of solid-state imaging devices 2c. In addition, the shape of the pair of solid-state imaging devices 2c is not limited to this, and may be any shape as long as the through hole is formed in the approximate center by being arranged so that the recesses face each other. Even if a substantially circular imaging device as shown in FIG. 5 is formed by arranging and joining a pair of substantially arc-shaped solid-state imaging devices 2b so that the respective concave portions formed on the inner peripheral side face each other. good.

  FIG. 7 shows the imaging device 1 near the tip of vacuum tweezers (processing means) 23 which is a micromanipulator of a processing apparatus for sucking and moving a micropart (object) such as an electronic part (not shown) to a predetermined position. An example in which is attached is schematically shown. Although not shown in detail, the vacuum tweezers 23 is attached to a drive mechanism that can move in three axial directions of XYZ in order to attract and move a minute part to a predetermined position at the tip.

  As shown in FIG. 7, for example, the imaging device 1 is fixed by pressing bumps on the chip of the solid-state imaging device 2 and pressing the tip of the casing 24. Although not shown in detail, the casing 24 has a cylindrical cavity at the center, and can be attached to the outer periphery of the vacuum tweezers 23 with the vacuum tweezers 23 inserted therethrough. Various wirings of the solid-state imaging device 2 are configured to pass through the casing 24. Thus, by attaching the imaging device 1 near the tip of the vacuum tweezers 23 via the casing 24, the object can be reliably imaged, and the accuracy of the processing device can be improved without impairing operability. it can. The shape of the casing 24 attached to the vacuum tweezers 23 is not limited to this, and any shape can be used as long as it can be attached near the tip of the vacuum tweezers 23 with the solid-state imaging device 2 provided.

  In FIG. 7, the vacuum tweezers 23 are shown as an example of the manipulator to which the imaging device 1 is attached. However, the manipulator to be inserted into the through hole 4 is not limited to this, and other conventionally known manipulators are used. It is also possible to attach to. Further, the imaging device 1 may be arranged so that a gas or fluid such as a laser or air for processing an object is inserted into the through hole 4.

  Further, as shown in FIG. 8, the imaging device 1 including the substantially square solid-state imaging device 2 is attached to the distal end side of the casing 24 having an attachment region having a diameter larger than the size of the imaging device 1. Illumination means 25a, 25b may be arranged around the. In FIG. 8, the illuminating means 25a having the same wavelength is arranged so as to face each other, and the illuminating means 25a and the illuminating means 25b having different wavelengths are arranged therebetween.

  The embodiment of the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the scope of the idea of the present invention.

DESCRIPTION OF SYMBOLS 1 Imaging device 2-2c Solid-state image sensor 3 Pixel 4 Through-hole 10 Micro lens 13 Photodiode (photoelectric conversion element)
21 Light emitting element 22 Recess 23 Vacuum tweezers (processing means)
24 casing

Claims (6)

An imaging apparatus having a solid-state imaging device in which a plurality of pixels in which photoelectric conversion elements for photoelectrically converting incident light to generate signal charges are arranged are arranged two-dimensionally,
An imaging device, wherein a through-hole penetrating from the front surface to the back surface is provided in a substantially central portion of the imaging device.   The imaging apparatus according to claim 1, wherein the solid-state imaging device includes a plurality of microlenses that collect incident light on the plurality of pixels. The imaging apparatus has a pair of solid-state imaging elements in which a plurality of pixels in which photoelectric conversion elements that generate signal charges by photoelectrically converting incident light are arranged are two-dimensionally arranged,
Each of the pair of solid-state imaging devices is provided with a recess, and the through-hole is formed by arranging the pair of solid-state imaging devices so that the respective recesses face each other. The imaging apparatus according to claim 1 or 2.   The imaging device according to claim 1, wherein the solid-state imaging element includes a light emitting element.   The imaging apparatus according to claim 1, wherein the solid-state imaging device is a back-illuminated solid-state imaging device. A processing apparatus comprising the imaging device according to claim 1,
The processing apparatus, wherein the imaging device is arranged so that processing means for processing an object passes through the through hole.

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