Distance measuring module

Abstract

In a ranging module using a ToF (Time of Flight) method, light leakage of irradiation light toward a light receiving side is reduced. A first pixel region in which a plurality of first pixels receiving reflected light of irradiation light from a light source are arranged and a second pixel region in which second pixels are arranged between the first pixel region and the light source are provided on a light receiving surface of a sensor chip. The light shielding wall is disposed between the first pixel region and the second pixel region. The sensor chip is connected to the support substrate and is formed with an opening that guides the reflected light to the first pixel region and the second pixel region.

Description

Technical Field

[0001] The present technical content relates to a distance measurement module. More specifically, the present technical content relates to a distance measurement module that emits irradiated light and receives reflected light. Background Art

[0002] For the distance measurement module, a distance measurement method called the time of flight (ToF) method is known. The ToF method is a method of measuring the distance by irradiating an object with irradiation light from an electronic device and obtaining the round-trip time required until the irradiation light is reflected back to the electronic device. For example, a module has been proposed in which a light-emitting element that emits irradiation light and a light-receiving element that receives reflected light are provided on a substrate, and a light-shielding wall is provided between these elements (for example, see Patent Document 1). In this module, a gap is formed between the light-shielding wall and the substrate so that the lower surface of the light-shielding wall does not contact the substrate.

[0003] List of existing technologies

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-27657 Summary of the invention

[0006] Problems to be solved by the present invention

[0007] With the above conventional technology, a gap is formed so that the lower surface of the light shielding wall does not contact the substrate. With this arrangement, the thermal expansion of the light shielding wall does not affect the substrate, and the sensing performance is enhanced. However, in the above module, the irradiated light may leak toward the light receiving side through the gap under the light shielding wall.

[0008] The present technical content has been proposed in view of such circumstances, and aims to reduce the leakage of illumination light toward the light receiving side in a distance measurement module using the ToF method.

[0009] Means of solving the problem

[0010] In order to solve the above problems, the present technical content has been proposed, and its first aspect is a distance measurement module, including: a sensor chip, a first pixel area and a second pixel area are arranged on the light receiving surface of the sensor chip, the first pixel area is arranged with a plurality of first pixels receiving reflected light of the irradiated light from a light source, the second pixel area is located between the first pixel area and the light source and is arranged with second pixels; a light shielding wall, the light shielding wall is arranged between the first pixel area and the second pixel area; and a supporting substrate, the sensor chip is connected to the supporting substrate, the supporting substrate is formed with an opening for guiding the reflected light to the first pixel area and the second pixel area. This brings about the effect of reducing the leakage of the irradiated light toward the light receiving side.

[0011] Furthermore, in the first aspect, the opening may include a first opening and a second opening separated by a bridge portion as a part of the support substrate, the first opening may guide the reflected light to the first pixel region, and the second opening may guide the reflected light to the second pixel region. This brings about an effect of reliably reducing light leakage.

[0012] In addition, in the first aspect, the light shielding wall may be provided in the bridge portion, and the width of the light shielding wall may be smaller than the distance between the first pixel region and the second pixel region. This brings about an effect of preventing reflected light from being shielded.

[0013] In addition, in the first aspect, the distance measuring module may further include: a laser chip in which a plurality of laser diodes as the light source are arranged; and a driver chip in which laser diode drivers for driving the plurality of laser diodes are respectively provided. In the distance measuring module, the sensor chip may be connected to the back side of the support substrate opposite to the front side as the surface on the light receiving side. This brings about the effect of causing the laser driver to emit light when the laser driver is driven by the laser diode driver.

[0014] In addition, in the first aspect, the laser chip may be disposed between the second pixel and the driver chip. This brings about an effect of causing the light reflected in the distance measuring module to enter the second pixel.

[0015] In addition, in the first aspect, the laser chip and the driver chip may be connected to the front surface of the support substrate. This brings about an effect of increasing the degree of freedom in selecting the laser diode and the laser diode driver.

[0016] In addition, in the first aspect, the laser chip and the driver chip may be connected to the back side of the support substrate, and the opening may further include a third opening for guiding the irradiation light from the laser chip. This brings about the effect of reducing the area and thickness of the distance measurement module.

[0017] In addition, in the first aspect, the laser chip may be connected to the back side of the support substrate, the driver chip may be connected to the front side of the support substrate, and the opening may further include a third opening for guiding the irradiation light from the laser chip. This brings about the effect of reducing the area of ​​the distance measurement module.

[0018] In addition, in the first aspect, the laser chip may be stacked on the driver chip. This brings about the effect of reducing the area of ​​the distance measurement module.

[0019] In addition, in the first aspect, the laser chip may be connected to the front surface of the support substrate by a wire. This brings about the effect of mounting the laser chip on the support substrate.

[0020] In addition, in the first aspect, the driver chip may be connected to the back surface of the support substrate by solder balls. This brings about the effect of reducing the thickness of the distance measurement module.

[0021] In addition, in the first aspect, the laser chip may be connected to the back surface of the support substrate, and the opening may further include a third opening that guides the irradiation light from the laser chip. This brings about an effect of reducing the thickness of the distance measuring module.

[0022] Moreover, in the first aspect, the distance measurement module may further include a distance measurement processing unit. In the distance measurement module, the second pixel may include a reference pixel, and the distance measurement processing unit may calculate the distance based on the time from the moment when the reference pixel receives light to the moment when the first pixel receives light. This brings about the effect of being able to obtain the light emission moment even if there is a time delay from the light emission instruction to the light emission.

[0023] In addition, in the first aspect, the distance measurement module may further include a control circuit. In the distance measurement module, the first pixel may include a first photodiode, the second pixel may include a monitoring pixel, the monitoring pixel may include a second photodiode and a sample-and-hold circuit, and when the cathode potential of the second photodiode decreases when the monitoring pixel receives light, the higher the potential maintained by the sample-and-hold circuit, the lower the potential provided by the control circuit to the anodes of the first photodiode and the second photodiode. This brings about the effect of suppressing fluctuations in excessive bias. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is an example of a cross-sectional view of a distance measuring module according to the first embodiment of the present technology.

[0025] Figure 2 is an example of a perspective view of a distance measuring module according to the first embodiment of the present technology.

[0026] Figure 3 1 is an example of a cross-sectional view of the distance measuring module according to the first embodiment of the present technology when viewed from another direction.

[0027] Figure 4 is a block diagram showing an example configuration of a distance measurement module according to a first embodiment of the present technology.

[0028] Figure 5: is a block diagram showing an example configuration of a solid-state imaging element according to a first embodiment of the present technology.

[0029] Figure 6 : is a block diagram showing an example configuration of a signal processing unit according to a first embodiment of the present technology.

[0030] Figure 7 are examples of perspective views and cross-sectional views of a distance measuring module according to a comparative example.

[0031] Figure 8 : is a block diagram showing an example configuration of a monitoring pixel, a measuring pixel, and a control unit according to a modification example of the first embodiment of the present technology.

[0032] Fig. 9 is a circuit diagram showing an example configuration of a control unit according to a first embodiment of the present technology.

[0033] Fig.10 : is a graph showing an example of fluctuations in cathode potential and anode potential according to the first embodiment of the present technology.

[0034] Fig.11 is an example of a cross-sectional view of a distance measuring module according to a second embodiment of the present technology.

[0035] Fig.12 is an example of a perspective view of a distance measuring module according to a second embodiment of the present technology.

[0036] Fig.13 is an example of a cross-sectional view of a distance measuring module according to a third embodiment of the present technology.

[0037] Fig.14 is an example of a cross-sectional view of a distance measuring module according to a fourth embodiment of the present technology.

[0038] Fig.15 is an example of a perspective view of a stacked chip according to a fourth embodiment of the present technology.

[0039] Fig.16 is an example of a cross-sectional view of a distance measuring module according to a fifth embodiment of the present technology.

[0040] Fig.17 is an example of a cross-sectional view of a distance measuring module according to a sixth embodiment of the present technology.

[0041] Fig.18 is a block diagram depicting an example of a schematic configuration of a vehicle control system.

[0042] Fig.19 is an explanatory diagram depicting an example of an installation position of an imaging unit. DETAILED DESCRIPTION

[0043] A method of implementing the present technical content (hereinafter referred to as an embodiment) will be described below. The description will be given in the following order.

[0044] 1. First Embodiment (Example in which the sensor chip is attached to the back surface of the support substrate)

[0045] 2. Second Embodiment (Example in which all chips are connected to the back surface of the supporting substrate)

[0046] 3. Third Embodiment (Example in which the sensor chip and the laser chip are attached to the back surface of the support substrate)

[0047] 4. Fourth Embodiment (Example in which the sensor chip is connected to the back surface of the support substrate, and the stacked chip is bonded to the front surface of the support substrate by wires)

[0048] 5. Fifth Embodiment (Example in which the sensor chip is connected to the back surface of the support substrate, and the stacked chip is connected to the front surface of the support substrate via solder balls)

[0049] 6. Sixth Embodiment (Example in which the sensor chip and the stacked chip are attached to the back surface of the support substrate)

[0050] 7. Application examples of mobile objects

[0051] <1. First Implementation>

[0052] [Example configuration of ranging module]

[0053] Figure 1 is an example of a cross-sectional view of the distance measuring module 100 according to the first embodiment of the present technology. In the drawings, "a" shows a cross-sectional view of the distance measuring module 100 having a suitable size, and "b" shows a cross-sectional view of the distance measuring module 100 having an inappropriate size.

[0054] The distance measuring module 100 measures a distance to an object, and includes lenses 111 and 112 , a sealing member 120 , an optical filter 122 , a support substrate 130 , a laser chip 140 , a driver chip 150 , and a sensor chip 200 .

[0055] In addition, the optical axis of the lenses 111 and 112 is defined as the Z axis, and a predetermined axis perpendicular to the Z axis is defined as the X axis. An axis perpendicular to the X axis and the Z axis is defined as the Y axis. This figure shows a cross-sectional view of the distance measurement module 100 when viewed from the Y axis direction.

[0056] The sensor chip 200 is a chip arranged with pixels that perform photoelectric conversion on incident light, and includes a stacked pixel chip 201 and a circuit chip 202. These chips are electrically connected via a connection portion (such as a via). It should be noted that in addition to vias, connection can also be made by Cu-Cu bonding or bumps. Connection can also be made by schemes other than these schemes (such as magnetic coupling). In addition, although two chips are stacked, three or more layers can be stacked. Alternatively, although the sensor chip 200 has a stacked structure, a single semiconductor chip can also be formed without stacking.

[0057] In the pixel chip 201, a plurality of pixels are arranged. These pixels include a plurality of measurement pixels 230 and a predetermined number of reference pixels 240. Hereinafter, the direction from the circuit chip 202 toward the pixel chip 201 is referred to as the "upward" direction, and the opposite direction is referred to as the "downward" direction.

[0058] A plurality of measurement pixels 230 are arranged in a two-dimensional lattice pattern in a measurement pixel region 221 on the upper surface of the pixel chip 201. At the same time, reference pixels 240 are arranged in a reference pixel region 222 on the upper surface of the pixel chip 201. In the drawings, the measurement pixels 230 are arranged two-dimensionally along the X-axis direction and the Y-axis direction, and the reference pixels 240 are also arranged two-dimensionally along the X-axis direction and the Y-axis direction. It should be noted that the measurement pixels 230 are examples of first pixels described in the claims, and the reference pixels 240 are examples of second pixels described in the claims. Moreover, the reference pixels 240 may be arranged one-dimensionally along the Y-axis direction, etc.

[0059] In addition, in the X-axis direction, a certain distance is maintained between the measurement pixel region 221 and the reference pixel region 222. In the drawing, the distance from the coordinate X2 to the coordinate X7 corresponds to the distance between the measurement pixel region 221 and the reference pixel region 222.

[0060] In addition, the peripheries of the pixels (the measurement pixels 230 and the reference pixels 240 ) on the upper surface of the pixel chip 201 are electrically connected (in other words, flip-chip mounted) to the lower surface of the support substrate 130 through the bumps 209 .

[0061] Two openings penetrating along the Z-axis direction are formed in the support substrate 130. The opening from the coordinate X1 to the coordinate X3 guides the reflected light of the irradiated light to the measurement pixel area 221, and the opening from the coordinate X6 to the coordinate X8 guides the reflected light to the reference pixel area 222. Hereinafter, a portion of the support substrate 130 from the coordinate X3 to the coordinate X6 that separates these openings from each other is referred to as a "bridge portion". Note that the former opening is an example of a first opening described in the claims, and the latter opening is an example of a second opening described in the claims.

[0062] In addition, the surface on the light receiving side of the support substrate 130 is called the upper surface or “front surface”, and the surface opposite to the upper surface is called the lower surface or “back surface.” The laser chip 140 and the driver chip 150 are electrically connected to the front surface of the support substrate 130 through wires 149 and 159 .

[0063] A plurality of laser diodes (not shown) are arranged as light sources on the laser chip 140. In addition, a laser diode driver (not shown) is provided on the driver chip 150. The laser driver diode drives each of the plurality of laser diodes to emit irradiation light. For example, as the irradiation light, invisible light (such as infrared light) is used.

[0064] In addition, in the X-axis direction, the reference pixel region 222 is disposed between the laser chip 140 and the measurement pixel region 221. The position of the driver chip 150 is not limited, but is disposed near the laser chip 140.

[0065] In the drawings, the laser chip 140 and the driver chip 150 are not stacked. Therefore, the degree of freedom in selecting a laser diode or a laser diode driver is higher than the degree of freedom in the case where these chips are stacked, as described below. In addition, the sensor chip 200 is connected to the back side of the support substrate 130, and the laser chip 140 is connected to the front side of the support substrate 130. Therefore, compared with the case where both of these chips are connected to the back side, wiring interference between the chips can be eliminated. This makes it easier to shorten the baseline length from the light source (laser chip 140) to the light receiving unit (measurement pixel area 221).

[0066] The sealing member 120 covers and seals the two openings of the support substrate 130 and the peripheries of the laser chip 140 and the driver chip 150 with the outer wall. In the sealing member 120, openings for attaching lenses 111 and 112 are formed. The lens 111 is attached to a portion located above the measurement pixel region 221, and the lens 112 is attached to a portion located above the laser chip 140.

[0067] The lens 111 condenses reflected light of the irradiation light and guides the reflected light to the measurement pixel area 221 below the lens 111. The lens 112 optically adjusts the irradiation light from the laser chip 140 below the lens 112, and uses a collimator lens or the like.

[0068] In addition, a portion of the outer wall of the sealing member 120 extends downward, and its lower end contacts the bridge portion of the support substrate 130. This portion serves as a light shielding wall 121 that shields the irradiated light. The light shielding wall 121 extends in the Y-axis direction, and the space inside the sealing member 120 is separated into two spaces on the light receiving side and the irradiation side by the light shielding wall 121. In the drawings, the portion from the coordinate X4 to the coordinate X5 corresponds to the light shielding wall 121.

[0069] The optical filter 122 passes light (infrared light or the like) in the same wavelength region as the irradiation light, and is provided between the lens 111 and the measurement pixel region 221 .

[0070] In addition, as shown in the example of "a" of the drawing, the width of each of the bridge portion and the light shielding wall 121 is considered to be narrower than the distance (the distance from the coordinate X2 to the coordinate X7) between the measurement pixel region 221 and the reference pixel region 222. In "a" of the drawing, the distance from the coordinate X3 to the coordinate X6 is the width of the bridge portion, and the distance from the coordinate X4 to the coordinate X5 is the width of the light shielding wall 121.

[0071] On the other hand, "b" of the accompanying drawing shows an inappropriate example in which the respective widths of the bridge portion and the light shielding wall 121 are equal to or greater than the distance (the distance from the coordinate X2 to the coordinate X7) between the measurement pixel region 221 and the reference pixel region 222. In this example, there is a possibility that a portion of the reflected light is blocked by the bridge portion and the light shielding wall 121. As shown in the example in "a" of the accompanying drawing, the widths of the bridge portion and the light shielding wall 121 are reduced to prevent blocking of a portion of the reflected light.

[0072] In summary, the measurement pixel region 221 and the reference pixel region 222 are formed on the light receiving surface of the sensor chip 200. In the measurement pixel region 221, a plurality of measurement pixels 230 that receive reflected light of irradiation light from the light source (laser chip 140) are arranged. The reference pixel region 222 is provided between the measurement pixel region 221 and the light source, and a predetermined number of reference pixels 240 are arranged therein. The light shielding wall 121 is provided between the measurement pixel region 221 and the reference pixel region 222.

[0073] In addition, two openings separated by a bridge portion from coordinate X3 to coordinate X6 are formed in the support substrate 130. One of the openings guides the reflected light to the measuring pixel region 221, and the other opening guides the reflected light to the reference pixel region 222. The former reflected light is light reflected by an object outside the ranging module 100, and the latter reflected light is light reflected inside the ranging module 100.

[0074] Note that an optical member (eg, a reflective mirror) that reflects the irradiated light and guides the reflected light to the reference pixel region 222 may be further provided inside the sealing member 120 .

[0075] Figure 2 1 is an example of a perspective view of the distance measuring module 100 according to the first embodiment of the present technology. In the drawings, "a" shows a perspective view of the distance measuring module 100, in which the lens 111, the lens 112, the sealing member 120, and the optical filter 122 have been removed. In the drawings, "b" shows a perspective view of the state in which the light shielding wall 121 is added in the drawing "a".

[0076] As shown in the example of the figure "a", the opening formed in the area surrounded by the coordinates (X1, Y1), (X1, Y2), (X3, Y1) and (X3, Y2) in the XY plane guides the reflected light to the measurement pixel 230. In addition, the opening formed in the area surrounded by the coordinates (X6, Y3), (X6, Y4), (X8, Y3) and (X8, Y4) guides the reflected light to the reference pixel 240. These openings are separated by a bridge portion in the area surrounded by the coordinates (X3, Y1), (X3, Y2), (X6, Y3) and (X6, Y4). It should be noted that the distance from Y1 to Y2 and the distance from Y3 to Y4 may be the same or different.

[0077] As shown in the example of the accompanying drawing "b", the light shielding wall 121 is provided in the bridge portion, and the lower end of the light shielding wall 121 contacts the bridge portion. Alternatively, a slight gap is left between the lower end of the light shielding wall 121 and the bridge portion within the range of avoiding the influence of the leakage of the irradiation light on the light receiving side. Since there is almost no gap between the bridge portion and the light shielding wall 121, the leakage of the irradiation light toward the light receiving side can be prevented.

[0078] It should be noted that although the two openings are separated by a bridge portion, the bridge portion may not be provided, and only one opening may be provided. In this case, a gap is formed between the lower end of the light shielding wall 121 and the upper surface of the sensor chip 200. However, the gap is located at a lower position than the light source, so light leakage hardly occurs. In addition, since only one opening needs to be formed, processing is easier.

[0079] Figure 3 2 is an example of a cross-sectional view of the distance measuring module 100 according to the first embodiment of the present technology when viewed from the X-axis direction. Figure 3 In the figure, "a" shows the Figure 2 The cross-sectional view taken along the line A1-A2 located directly below the light shielding wall 121 in "b" of FIG. Figure 3 , "b" shows the Figure 2 'b' is a cross-sectional view taken along line B1 - B2 extending through the opening.

[0080] like Figure 3 As shown in the example of "a" in FIG. 1 , the lower end of the light shielding wall 121 contacts the bridge portion of the support substrate 130. Figure 3 As shown in the example of "b", the portion from coordinate Y3 to coordinate Y4 is open.

[0081] Figure 4 1 is a block diagram showing an example configuration of a distance measurement module 100 according to a first embodiment of the present technology. The distance measurement module 100 includes a laser chip 140 , a driver chip 150 , and a sensor chip 200 .

[0082] A plurality of laser diodes 141 are arranged in the laser chip 140 . For example, a vertical cavity surface emitting laser (VCSEL) is used as the laser diode 141 . A laser diode driver 151 is provided in the driver chip 150 . A solid-state imaging element 205 is provided in the sensor chip 200 .

[0083] The laser diode 141 emits light in response to the driving of the laser diode driver 151. The laser diode driver 151 drives the laser diode 141 according to the light emission instruction supplied from the solid-state imaging element 205.

[0084] In addition, the solid-state imaging element 205 measures the distance from each measurement pixel 230 to the object by a direct ToF (dToF) method, and outputs distance data.

[0085] [Example configuration of solid-state imaging element]

[0086] Figure 5 2 is a block diagram showing an example configuration of a solid-state imaging element 205 according to a first embodiment of the present technology. The solid-state imaging element 205 includes a control circuit 210, a pixel array unit 220, and a signal processing unit 250. In the pixel array unit 220, a measurement pixel area 221 and a reference pixel area 222 are provided. A plurality of measurement pixels 230 are arranged in the measurement pixel area 221, and a predetermined number of reference pixels 240 are arranged in the reference pixel area 222. These pixels are arranged in a pixel chip 201. It should be noted that some elements in each pixel may be provided in the pixel chip 201, and the remaining elements may be provided in the circuit chip 202.

[0087] Each measuring pixel 230 includes a photodiode, for example, a single photon avalanche diode (SPAD), a resistor, and a transistor, and generates a pulse signal when reflected light enters. The circuit configuration of each reference pixel 240 is similar to that of each measuring pixel 230. However, as described above, the reference pixel 240 is disposed on the irradiation side of both sides of the light shielding wall 121. Therefore, the length of the optical path in which the irradiation light from the laser diode 141 is reflected in the distance measuring module 100 and enters the reference pixel 240 is extremely short.

[0088] The control circuit 210 controls the potential of each pixel. The signal processing unit 250 measures the distance for each measurement pixel 230 based on the signal from each measurement pixel 230 and each reference pixel 240 .

[0089] [Example configuration of signal processing unit]

[0090] Figure 6 2 is a block diagram showing an example configuration of a signal processing unit 250 according to a first embodiment of the present technology. The signal processing unit 250 includes a time-to-digital converter (TDC) 251 and a measurement processing unit 252 for each column. The pulse signal OUT output from the pixel (measurement pixel 230 or reference pixel 240) in one column is provided to the TDC 251 of the column. Note that a set of TDCs 251 and a measurement processing unit 252 for M pixels (M is an integer of 1 or more) may be provided just below the pixel array unit 220.

[0091] Each TDC 251 measures the time from the output timing of issuing a light emission instruction to the laser diode driver 151 to the rising timing of the pulse signal OUT (in other words, the light reception timing).

[0092] The measurement processing unit 252 measures the distance for each measurement pixel 230. The measurement processing unit 252 outputs a light emission instruction to the laser diode driver 151, and controls the TDC 251 of each column to start timing. Then, the TDC 251 of each column stops timing when the pulse signal of the corresponding column rises, and transmits time information indicating the timing time t to the measurement processing unit 252. Based on these times t, the measurement processing unit 252 generates a histogram.

[0093] Here, by the dToF method, distance measurement is performed based on the difference between the time t0 at which light is emitted by the light source (laser diode 141 ) and the time t1 at which light is received by the measuring pixel 230 , using the following expression.

[0094] D = (c / 2) × (t1 - t0) ... (Expression 1)

[0095] In the above expressions, for example, D represents distance, and the unit is meter (m). In addition, for example, c represents the speed of light, and the unit is meter per second (m / s).

[0096] As described above, the laser diode driver 151 drives the laser diode 141 according to the light emission instruction from the measurement processing unit 252, and causes the laser diode 141 to emit light. At this point in time, there is some time delay between the light emission instruction and the actual light emission from the laser diode 141. This time delay is caused by a time constant in the path from the measurement processing unit 252 to the laser diode 141, a characteristic change due to the temperature or aging of the laser diode 141, and the like, and is difficult to predict.

[0097] Therefore, as described above, the reference pixel 240 is arranged at a position where the optical path length from the laser diode 141 to the reference pixel 240 is extremely short. With this arrangement, the difference between the time when the reference pixel 240 receives light and the time when the light is emitted can be regarded as zero. Therefore, the time when the reference pixel 240 receives light can be regarded as the time when the light is emitted.

[0098] The measurement processing unit 252 creates a histogram by acquiring time information for each pixel multiple times (for example, thousands to tens of thousands of times), and acquires the peak of the created histogram as the time when the pixel receives light. Then, the measurement processing unit 252 specifies the time when the reference pixel 240 receives light as t0 in Expression 1, and specifies the time when the measurement pixel 230 receives light as t1 in Expression 1, thereby calculating the distance D of each measurement pixel 230. It is to be noted that Japanese Patent Application Laid-Open No. 2020-139810 discloses the details of the distance measurement method using the reference pixel 240.

[0099] Here, as a comparative example, a configuration in which any opening is not formed in the support substrate 130 and the sensor chip 200 is connected to the support substrate 130 is discussed.

[0100] Figure 7 1 is an example of a perspective view and a cross-sectional view of a distance measuring module according to a comparative example. In the accompanying drawings, the laser chip 140 and the driver chip 150 are not shown. In the accompanying drawings, "a" shows a perspective view of the comparative example, and "b" shows a cross-sectional view of the comparative example as viewed from the X-axis direction. In the accompanying drawings, "c" shows a cross-sectional view of the comparative example as viewed from the Y-axis direction.

[0101] As shown in the example of "a" of the accompanying drawings, in the comparative example, the sensor chip 200 is electrically connected to the support substrate 130 through the wire 139. Therefore, as shown in the examples of "b" and "c" of the accompanying drawings, a gap of a certain size is formed between the lower end of the light shielding wall 121 and the light receiving surface of the sensor chip 200, so that the lower end of the light shielding wall 121 does not contact the wire 139. In the configuration of the comparative example, the irradiation light may leak to the light receiving side through the gap. This makes it difficult to distinguish between the reflected light outside the ranging module 100 and the scattered light inside the ranging module 100. As a result, the short-distance measurement range is particularly limited. In addition, the peak separation between the internal scattered light and the reflected light requires a calculation cost. In order to avoid this, the measurement pixel 230 and the reference pixel 240 should be separated from each other. However, in that case, it is easy to cause different reflected light rays due to parallax to be received by one pixel, and it is difficult to detect the long-distance reflected light obtained simultaneously with the short-distance reflected light. In this case, missed detection of an object at a long distance occurs, or in other words, occlusion occurs.

[0102] On the other hand, in the case where an opening is formed in the support substrate 130 and the sensor chip 200 is a flip chip mounted on the back surface of the support substrate 130, Figure 1 In the configuration, there is no need to avoid the wires on the front side, and therefore, the lower end of the light shielding wall 121 can be in contact with the bridging portion of the support substrate 130. This can reduce the leakage of the irradiated light. When light leakage is reduced in this way, the ranging range on the short-distance side can be wider than the range in the comparative example. Moreover, peak separation between internal scattered light and reflected light becomes unnecessary, and the calculation cost can be reduced. In addition, the distance between the measuring pixel 230 and the reference pixel 240 can be closer to the width of the light shielding wall 121, and therefore, occlusion can be prevented.

[0103] As described above, according to the first embodiment of the present technology, an opening is formed in the support substrate 130, the sensor chip 200 is a flip chip mounted on the back surface of the support substrate 130, and the light shielding wall 121 is provided. Therefore, the gap at the lower end of the light shielding wall 121 can be omitted, and light leakage can be reduced.

[0104] [Modifications]

[0105] In the first embodiment described above, the solid-state imaging element 205 measures the distance assuming that the light-receiving moment of the reference pixel 240 is the light-emitting moment. However, a pixel different from the reference pixel 240 may be provided on the irradiation side. The distance-measuring module 100 according to the modification of the first embodiment differs from the first embodiment in that a monitoring pixel is provided instead of the reference pixel 240.

[0106] In a modification of the first embodiment, a monitoring pixel 401 is arranged instead of the reference pixel 240 , and a control unit 500 is further provided.

[0107] Figure 8 1 is a block diagram showing an example configuration of a monitoring pixel 401, a measuring pixel 230, and a control unit 500 according to a modification of the first embodiment of the present technology. In the control unit 500, an inter-pixel average acquisition unit 510, a time average acquisition unit 520, and a potential control unit 530 are provided.

[0108] Each monitoring pixel 401 includes a photoelectric conversion element 211 , a p-channel metal oxide semiconductor (pMOS) transistor 311 , a timing detection circuit 320 , a sample-and-hold circuit 330 , and buffers 340 and 350 .

[0109] The pMOS transistor 311 is inserted between the power supply potential VE and the photoelectric conversion element 211. In addition, the control signal RCH from the timing generation unit 220 is input to the gate of the pMOS transistor 311. When the control signal RCH of a low level is input, the pMOS transistor 311 supplies the power supply potential VE to a connection node 312 between the pMOS transistor 311 and the photoelectric conversion element 211.

[0110] According to the incident photon, the photoelectric conversion element 211 outputs a photocurrent through photoelectric conversion. For example, SPAD is used as the photoelectric conversion element 211. The cathode of the photoelectric conversion element 211 is connected to the connection node 312, and its cathode potential Vs corresponds to the potential of the monitoring target. On the other hand, the anode of the photoelectric conversion element 211 is connected to the control unit 500, and its anode potential VSPAD is controlled by the control unit 500.

[0111] The buffer 340 is inserted between the connection node 312 and the sample and hold circuit 330 .

[0112] The timing detection circuit 320 monitors the cathode potential Vs and detects the moment when a predetermined period of time has passed since the potential Vs began to decrease relative to the potential (power supply potential VE) provided by the pMOS transistor 311. When the cathode potential Vs is the monitoring target, when the photocurrent flows according to the incidence of photons, the cathode potential Vs is lower than the power supply potential VE. It should be noted that the monitoring pixel 401 can also monitor the anode potential as described below. When the anode potential is monitored, the moment when a predetermined period of time has passed since the anode potential began to increase is detected.

[0113] The sample and hold circuit 330 receives and holds the cathode potential Vs based on the timing detected by the timing detection circuit 320. The sample and hold circuit 330 outputs the held potential to the buffer 350 as a held potential Vs_SH.

[0114] The buffer 350 is inserted between the sample hold circuit 330 and the control unit 500. Note that the buffer 250 is not necessarily provided, and a configuration may be designed without providing the buffer 250. Alternatively, two or more buffers 340 and two or more buffers 350 may be provided.

[0115] In addition, the photoelectric conversion element 212 , the pMOS transistor 381 , and the inverter 382 are provided in each measurement pixel 230 .

[0116] The connection configuration between the pMOS transistor 381 and the photoelectric conversion element 212 is similar to the connection configuration between the pMOS transistor 311 and the photoelectric conversion element 211 in each monitoring pixel 401 .

[0117] The inverter 382 inverts the signal of the cathode potential of the photoelectric conversion element 212 , and supplies the inverted signal to the multiplexer 231 (or the multiplexer 232 ) as a pulse signal of the measurement pixel 230 .

[0118] In addition, each monitoring pixel 401 in the plurality of monitoring pixels 401 provides a holding potential Vs_SH to the inter-pixel average acquisition unit 510. The holding potential of the mth (m is an integer) monitoring pixel 401 is defined as Vs_SH m It is to be noted that the monitoring pixel 401 is an example of the second pixel of the claims.

[0119] The pixel average acquisition unit 510 calculates the holding potential Vs_SH of each of the plurality of monitoring pixels 401. m The average value is taken as the average value between pixels Vs_SH AVp The pixel average acquisition unit 510 converts the pixel average value Vs_SH AVp Provided to the time average acquisition unit 520.

[0120] The time average acquisition unit 520 calculates the average value Vs_SH between pixels AVp Time average value Vs_SH AVt The time average acquisition unit 520 converts the time average value Vs_SH AVt Provided to the potential control unit 530.

[0121] The time average value of the cathode potential Vs_SH AVt The higher the anode potential VSPAD is, the lower the potential control unit 530 controls the potential of the anode potential VSPAD. All anodes of the plurality of monitoring pixels 401 and the plurality of measuring pixels 230 are connected to the potential control unit 530, and the potential control unit 530 controls the potential of these anodes. It should be noted that when the monitoring pixel 401 monitors the anode potential, the cathode potential is controlled by the potential control unit 530.

[0122] In addition, in each monitoring pixel 401, one of the anode and the cathode of the photoelectric conversion element 211 (for example, the cathode) is connected to the connection node 312. The pMOS transistor 311 supplies the power supply potential VE to the connection node 312 according to the control signal RCH.

[0123] The timing detection circuit 320 detects the time when a predetermined period of time has passed since the cathode potential Vs of the connection node 312 began to fall relative to the power supply potential VE. This time corresponds to the time when a predetermined delay time has passed since the cathode potential fell to a value lower than the threshold of the inverter 321.

[0124] The sample and hold circuit 330 receives and holds the cathode potential Vs as a hold potential Vs_SH based on the timing detected by the timing detection circuit 320 .

[0125] Then, the higher the holding potential Vs_SH is, the lower the control unit 500 controls the potential of the other (for example, the anode) of the anode and the cathode of the photoelectric conversion element 211 .

[0126] In addition, in the monitoring pixel 401, the buffer 340 is inserted in the stage before the sample-hold circuit 330, so that the capacitance of the connection node of each monitoring pixel 401 and each measuring pixel 230 can be equalized. The connection node is a connection node between the photoelectric conversion element and the pMOS transistor. Therefore, the breakdown voltage VBD of each monitoring pixel 401 and each measuring pixel 230 can be equalized.

[0127] [Example configuration of control unit]

[0128] Fig. 9 is a circuit diagram showing an example configuration of a control unit 500 according to a first embodiment of the present technology. In the inter-pixel average acquisition unit 510, a plurality of resistors 511 and capacitors 512 are provided. The resistors 511 are provided for each monitoring pixel 401. In the time average acquisition unit 520, a variable resistor 521 and a variable capacitor 522 are provided. In the potential control unit 530, an amplifier 531 is provided.

[0129] In the inter-pixel average acquisition unit 510, one end of each resistor 511 is connected to each corresponding monitoring pixel 401, and the other end thereof is connected to one end of a capacitor 512 and the time average acquisition unit 520. That is, a plurality of resistors 511 are connected in parallel between a plurality of monitoring pixels 401 and capacitors 512. The other end of the capacitor 512 is connected to the ground potential. Through these resistors 511, the holding potential Vs_SH of the plurality of monitoring pixels 401 is generated. m The average potential between pixels is Vs_SH AVp, and is held in the capacitor 512. By obtaining an inter-pixel average value, adverse effects due to variations in the held potential Vs_SH between pixels can be suppressed.

[0130] In addition, in the time average acquisition unit 520, one end of the variable resistor 521 is connected to the inter-pixel average acquisition unit 510, and the other end is connected to one end of the variable capacitor 522 and the potential control unit 530. The other end of the variable capacitor 522 is connected to the ground potential. The circuit formed by the variable resistor 521 and the variable capacitor 522 serves as an analog low-pass filter that generates the inter-pixel average value Vs_SH AVp Time average value Vs_SH AVt .

[0131] In the potential control unit 530, the time average value Vs_SH Avt is input to the inverting input terminal (-) of the amplifier 531, and a predetermined power supply potential is input to the non-inverting input terminal (+) of the amplifier 531. The amplifier 531 generates a comparison result between these potentials as VSPAD according to the following expression, and supplies VSPAD to the anodes of the monitoring pixel 401 and the measuring pixel 230.

[0132] VSPAD = Av(VREF - Vs_SH AVt )

[0133] In the above expression, Av represents the gain of the amplifier 531, and VREF represents the target value of VSPAD.

[0134] Fig.10 3 is a diagram showing an example of fluctuation of the cathode potential Vs and the anode potential VSPAD according to the first embodiment of the present technology. The power supply potential VE is provided by the pMOS transistor 311, and the cathode potential Vs is the power supply potential VE. When a photon enters, the cathode potential Vs drops to the bottom potential VBT, and is restored to the initial power supply potential VE by recharging.

[0135] Here, the voltage between the power supply potential VE and the bottom potential VBT is called the overbias voltage VEX. In addition, the voltage between the bottom potential VBT and the anode potential VSPAD is called the breakdown voltage VBD. When the power supply potential VE and the anode potential VSPAD are constant, the overbias voltage VEX fluctuates with changes in the breakdown voltage VBD and temperature.

[0136] When the over-bias voltage VEX decreases, the sensitivity of the photodiode in the measuring pixel 230 decreases when a photon enters. In this case, even if a photon has entered, a pulse signal for the measuring pixel 230 is not generated, and the photon detection efficiency (PDE) will be low. Therefore, the higher the potential is maintained when the cathode potential Vs is reduced, the lower the anode potential VSPAD is made by the control unit 500. As a result, the breakdown voltage VBD becomes higher and the over-bias voltage VEX increases, thereby improving the PDE. It should be noted that Japanese Patent Application Laid-Open No. 2021-56016 discloses details of a potential control method using a monitoring pixel 401.

[0137] Note that, in the modification of the first embodiment, the monitoring pixel 401 is provided instead of the reference pixel 240 , but both the reference pixel 240 and the monitoring pixel 401 may be provided on the irradiation side.

[0138] As described above, according to the modification of the first embodiment of the present technology, the control circuit 210 makes the anode potential VSPAD lower as the holding potential is higher when the cathode potential Vs is lowered. Therefore, PDE can be increased.

[0139] <2. Second Embodiment>

[0140] In the first embodiment described above, the laser chip 140 and the driver chip 150 are connected to the front side of the support substrate 130. However, with this configuration, it is difficult to further reduce the thickness and area of ​​the ranging module 100. Here, the thickness refers to the dimension in the Z-axis direction. The ranging module 100 according to the second embodiment is different from the first embodiment in that the laser chip 140 and the driver chip 150 are connected to the back side of the support substrate 130.

[0141] Fig.11 1 is an example of a cross-sectional view of a distance measuring module 100 according to a second embodiment of the present technology. The distance measuring module 100 according to the second embodiment is different from the first embodiment in that a laser chip 140 and a driver chip 150 are flip chips mounted on the back surface of a support substrate 130 .

[0142] Moreover, in the support substrate 130, a third opening for guiding the irradiation light is further formed in the range from the coordinate X9 to the coordinate X10 below the lens 112. The laser chip 140 is connected directly below the opening with its light emitting surface facing upward. It should be noted that the opening from the coordinate X9 to the coordinate X10 is an example of the third opening of the claim.

[0143] As shown in the example in the drawings, an opening is added, and the laser chip 140 and the driver chip 150 are connected to the back side of the support substrate 130, so that the chips and wires on the front side of the support substrate 130 can be reduced. As a result, the thickness of the sealing member 120 can be reduced by an amount equivalent to the eliminated chips and wires, and the thickness of the ranging module 100 can be reduced by that amount. In addition, it is no longer necessary to seal the chip in the sealing member 120, and therefore, the area of ​​the sealing member 120 can be smaller than that in the first embodiment.

[0144] In addition, the laser chip 140 and the driver chip 150 are connected by bumps, so that the wiring length can be shortened and the parasitic inductance can be lowered compared to the first embodiment in which bonding is performed by wires. Therefore, the output of the laser diode 141 can be increased to achieve longer distance measurement.

[0145] Fig.12 1 is an example of a perspective view of the distance measuring module 100 according to the second embodiment of the present technology. As shown in the example in the drawing, an opening for guiding the irradiation light from the laser diode 141 is added on the irradiation side.

[0146] Note that the modification of the first embodiment may be applied to the second embodiment.

[0147] As described above, according to the second embodiment of the present technology, an opening is added to the support substrate 130, and the laser chip 140 and the driver chip 150 are connected to the back side of the support substrate 130. Therefore, the thickness of the ranging module 100 can be reduced, and the area of ​​the ranging module 100 can be made smaller.

[0148] <3. Third Implementation>

[0149] In the first embodiment described above, the laser chip 140 is connected to the front side of the support substrate 130. However, with this configuration, it is difficult to further reduce the area of ​​the distance measuring module 100. The distance measuring module 100 according to the third embodiment is different from the first embodiment in that the laser chip 140 is connected to the back side of the support substrate 130.

[0150] Fig.13 1 is an example of a cross-sectional view of a distance measuring module 100 according to a third embodiment of the present technology. The distance measuring module 100 according to the third embodiment is different from the first embodiment in that a laser chip 140 is a flip chip mounted on the back surface of a support substrate 130 .

[0151] Also, a third opening for guiding the irradiation light is further formed in the support substrate 130. The laser chip 140 is connected just below the opening with its light emitting surface facing upward.

[0152] As shown in the example in the drawings, an opening is added and the laser chip 140 is connected to the back side of the support substrate 130, so that the laser chip 140 and the wire 149 on the front side of the support substrate 130 can be reduced. Since the space on the front surface required for the wire 149 connecting the laser chip 140 is no longer required, the area of ​​the distance measurement module 100 can be reduced by a corresponding amount.

[0153] Note that the modification of the first embodiment may be applied to the third embodiment.

[0154] As described above, according to the third embodiment of the present technology, an opening is added to the support substrate 130, and the laser chip 140 is connected to the back surface of the support substrate 130. Therefore, the area of ​​the distance measuring module 100 can be made smaller.

[0155] <4. Fourth Implementation>

[0156] In the first embodiment described above, the laser chip 140 and the driver chip 150 are bonded to the front surface of the support substrate 130 by wires. However, with this configuration, it is difficult to further reduce the area of ​​the ranging module 100. The ranging module 100 according to the fourth embodiment is different from the first embodiment in that the laser chip 140 and the driver chip 150 are stacked.

[0157] Fig.14 1 is an example of a cross-sectional view of a distance measuring module 100 according to a fourth embodiment of the present technology. The distance measuring module 100 of the fourth embodiment is different from the first embodiment in that a laser chip 140 is stacked on the upper surface of a driver chip 150 with its light emitting surface facing upward. The stacked chips are electrically connected to the front side of a support substrate 130 through a wire 149.

[0158] As shown in the example of the drawing, the laser chip 140 is stacked on the driver chip 150, so that the area required for mounting the chip on the support substrate 130 can be smaller than that in the first embodiment. Therefore, the area of ​​the distance measurement module 100 can be smaller than that in the first embodiment.

[0159] exist Fig.14 In the embodiment, the areas of the driver chip 150 and the laser chip 140 are substantially the same as each other, but the present embodiment is not limited to this configuration. Fig.15 As shown in the example in FIG. 1 , the area of ​​the laser chip 140 located on the upper side may be smaller than the area of ​​the driver chip 150 .

[0160] Note that the modification example of the first embodiment may be applied to the fourth embodiment.

[0161] As described above, according to the fourth embodiment of the present technology, the laser chip 140 is stacked on the driver chip 150 , and thus the area of ​​the distance measuring module 100 can be made smaller.

[0162] <5. Fifth Implementation>

[0163] In the fourth embodiment described above, wire bonding of a stacked chip formed by stacking the laser chip 140 and the driver chip 150 is performed. However, with this configuration, it is difficult to further reduce the thickness of the ranging module 100. The ranging module 100 according to the fifth embodiment is different from the first embodiment in that the stacked chips are connected by solder balls.

[0164] Fig.16 is an example of a cross-sectional view of a distance measuring module 100 according to a fifth embodiment of the present technology. The distance measuring module 100 of the fifth embodiment is different from the first embodiment in that a stacked chip formed of a laser chip 140 and a driver chip 150 is electrically connected to a support substrate 130 through a plurality of solder balls 148 arranged in an array. Such a chip is called a ball grid array (BGA).

[0165] As shown in the example in the drawing, BGA is used as a stacked chip, so that the wires on the front side of the support substrate 130 can be reduced. Therefore, the thickness of the sealing member 120 can be reduced by an amount equivalent to the eliminated wires, and the thickness of the ranging module 100 can be reduced by that amount.

[0166] Note that the modification of the first embodiment may be applied to the fifth embodiment.

[0167] As described above, according to the fifth embodiment of the present technology, BGA is used as a stacked chip formed of the laser chip 140 and the driver chip 150 , and thus, the thickness of the distance measuring module 100 can be reduced.

[0168] <6. Sixth Implementation Method>

[0169] In the first embodiment described above, the laser chip 140 and the driver chip 150 are bonded to the front side of the support substrate 130 by wires. However, with this configuration, it is difficult to further reduce the thickness and area of ​​the ranging module 100. The ranging module 100 according to the sixth embodiment is different from the first embodiment in that the laser chip 140 and the driver chip 150 are stacked and then connected to the back side of the support substrate 130.

[0170] Fig.171 is an example of a cross-sectional view of a distance measuring module 100 according to a sixth embodiment of the present technology. The distance measuring module 100 of the sixth embodiment is different from the first embodiment in that a laser chip 140 is stacked on the upper surface of a driver chip 150 with its light emitting surface facing upward. The stacked chip is a flip chip mounted on the back side of a support substrate 130.

[0171] Also, a third opening for guiding the irradiation light is further formed in the range from the coordinate X9 to the coordinate X10 in the support substrate 130. The stacked chip is connected just below the opening with the light emitting surface thereof facing upward.

[0172] As shown in the example in the drawings, an opening is added, and a stacked chip formed of a laser chip 140 and a driver chip 150 is connected to the back side of the support substrate 130, so that the chips and wires on the front side of the support substrate 130 can be reduced. As a result, the thickness of the sealing member 120 can be reduced by an amount equivalent to the eliminated chips and wires, and the thickness of the ranging module 100 can be reduced by that amount. In addition, it is no longer necessary to seal the chip in the sealing member 120, and therefore, the area of ​​the sealing member 120 can be smaller than that in the first embodiment.

[0173] Note that the modification example of the first embodiment may be applied to the sixth embodiment.

[0174] As described above, according to the fifth embodiment of the present technology, an opening is added to the support substrate 130, and the stacked chip is connected to the back side of the support substrate 130. Therefore, the thickness of the distance measuring module 100 can be reduced, and the area of ​​the distance measuring module 100 can be made smaller.

[0175] <7. Application examples of mobile objects>

[0176] The technology according to the present disclosure (the present technology) can be used in various products. For example, the technology according to the present disclosure can be implemented as a device installed on any type of mobile body such as a car, an electric car, a hybrid electric car, a motorcycle, a bicycle, a personal mobile device, an airplane, a drone, a ship, or a robot.

[0177] Fig.18 is a block diagram depicting an example of a schematic configuration of a vehicle control system as an example of a moving body control system to which the technology according to the embodiment of the present disclosure can be applied.

[0178] The vehicle control system 12000 includes a plurality of electronic control units connected to each other via a communication network 12001. Fig.18In the depicted example, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an exterior information detection unit 12030, an interior information detection unit 12040, and an integrated control unit 12050. In addition, a microcomputer 12051, a sound / image output portion 12052, and an in-vehicle network interface (I / F) 12053 are shown as functional components of the integrated control unit 12050.

[0179] The drive system control unit 12010 controls the operation of devices related to the drive system of the vehicle according to various programs. For example, the drive system control unit 12010 serves as a control device for a drive force generating device for generating a drive force of the vehicle, such as an internal combustion engine, a drive motor, etc., a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, a braking device for generating a braking force of the vehicle, etc.

[0180] The body system control unit 12020 controls the operation of various devices provided on the vehicle body according to various programs. For example, the body system control unit 12020 serves as a control device for a keyless entry system, a smart key system, a power window device, or various lights (such as headlights, reverse lights, brake lights, turn signals, fog lights, etc.). In this case, radio waves transmitted from a mobile device as a key replacement or signals of various switches may be input to the body system control unit 12020. The body system control unit 12020 receives these input radio waves or signals and controls the door lock device, power window device, lights, etc. of the vehicle.

[0181] The vehicle exterior information detection unit 12030 detects information about the exterior of the vehicle including the vehicle control system 12000. For example, the vehicle exterior information detection unit 12030 is connected to the imaging unit 12031. The vehicle exterior information detection unit 12030 causes the imaging unit 12031 to image the exterior of the vehicle and receives the imaged image. Based on the received image, the vehicle exterior information detection unit 12030 can perform detection processing of objects such as people, vehicles, obstacles, signs, characters on the road surface, or detection processing of the distance thereto.

[0182] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal corresponding to the amount of light received. The imaging unit 12031 may output the electrical signal as an image, or may output the electrical signal as information about the measured distance. In addition, the light received by the imaging unit 12031 may be visible light or invisible light such as infrared rays.

[0183] The in-vehicle information detection unit 12040 detects information about the interior of the vehicle. For example, the in-vehicle information detection unit 12040 is connected to a driver state detection part 12041 that detects the driver's state. For example, the driver state detection part 12041 includes a camera that takes a picture of the driver. Based on the detection information input from the driver state detection part 12041, the in-vehicle information detection unit 12040 can calculate the driver's fatigue level or the driver's concentration level, or can determine whether the driver is dozing off.

[0184] Based on the information about the interior or exterior of the vehicle obtained by the vehicle exterior information detection unit 12030 or the vehicle interior information detection unit 12040, the microcomputer 12051 can calculate the control target value of the driving force generating device, the steering mechanism or the braking device, and output a control instruction to the driving system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of the advanced driver assistance system (ADAS), such as collision avoidance or shock absorption of the vehicle, following driving based on the following distance, speed maintenance driving, vehicle collision warning, vehicle lane departure warning, etc.

[0185] In addition, based on information about the outside or inside of the vehicle obtained by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040, the microcomputer 12051 can perform collaborative control aimed at automatic driving by controlling the driving force generating device, steering mechanism, braking device, etc., which enables the vehicle to drive automatically without relying on the driver's operation, etc.

[0186] In addition, based on the information about the outside of the vehicle obtained by the vehicle exterior information detection unit 12030, the microcomputer 12051 can output a control instruction to the body system control unit 12020. For example, the microcomputer 12051 can perform cooperative control aimed at preventing glare by controlling the headlights to change from high beam to low beam, for example, according to the position of the preceding vehicle or oncoming vehicle detected by the vehicle exterior information detection unit 12030.

[0187] The sound / image output portion 12052 transmits an output signal of at least one of sound and image to an output device, and the output device can notify information to vehicle passengers or the outside of the vehicle in a visual or auditory manner. Fig.18 In the example of FIG. 1 , an audio speaker 12061, a display portion 12062, and a dashboard 12063 are shown as output devices. For example, the display portion 12062 may include at least one of an in-vehicle display and a head-up display.

[0188] Fig.19 is a diagram depicting an example of the installation position of the imaging unit 12031.

[0189] exist Fig.19 In the figure, imaging unit 12031 includes imaging units 12101, 12102, 12103, 12104 and 12105.

[0190] For example, imaging units 12101, 12102, 12103, 12104, and 12105 are disposed at positions on the front of the vehicle 12100, the side mirrors, the rear bumper, and the rear door, and at positions on the upper portion of the windshield inside the vehicle. The imaging unit 12101 disposed at the front of the vehicle and the imaging unit 12105 disposed at the upper portion of the windshield inside the vehicle mainly obtain images in front of the vehicle 12100. The imaging units 12102 and 12103 disposed at the side mirrors mainly obtain images of the sides of the vehicle 12100. The imaging unit 12104 disposed at the rear bumper or the rear door mainly obtains images of the rear of the vehicle 12100. The imaging unit 12105 disposed at the upper portion of the windshield inside the vehicle is mainly used to detect vehicles ahead, pedestrians, obstacles, signals, traffic signs, lanes, and the like.

[0191] Please note that Fig.19 An example of the imaging ranges of the imaging units 12101 to 12104 is depicted. Imaging range 12111 indicates the imaging range of the imaging unit 12101 provided at the front of the vehicle. Imaging ranges 12112 and 12113 respectively indicate the imaging ranges of the imaging units 12102 and 12103 provided at the side mirrors. Imaging range 12114 indicates the imaging range of the imaging unit 12104 provided at the rear bumper or the rear door. For example, a bird's-eye view image of the vehicle 12100 observed from above is obtained by superimposing image data imaged by the imaging units 12101 to 12104.

[0192] At least one of the imaging units 12101 to 12104 may have a function of obtaining distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera composed of a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection.

[0193] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 can determine the distance to each three-dimensional object within the imaging ranges 12111 to 12114 and the change in distance over time (relative speed with respect to the vehicle 12100), thereby extracting the nearest three-dimensional object as the leading vehicle, in particular, the nearest three-dimensional object that exists on the driving path of the vehicle 12100 and travels in substantially the same direction as the vehicle 12100 at a predetermined speed (e.g., equal to or greater than 0 km / h). In addition, the microcomputer 12051 can pre-set the following distance to be maintained in front of the leading vehicle, and perform automatic braking control (including following vehicle stop control), automatic acceleration control (including following vehicle start control), etc. Therefore, cooperative control aimed at automatic driving can be performed to make the vehicle travel automatically without relying on the operation of the driver, etc.

[0194] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 can classify the three-dimensional object data on the three-dimensional object into three-dimensional object data of two-wheeled vehicles, standard-sized vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects, extract the classified three-dimensional object data, and use the extracted three-dimensional object data to automatically avoid obstacles. For example, the microcomputer 12051 identifies obstacles around the vehicle 12100 as obstacles that can be visually recognized by the driver of the vehicle 12100 and obstacles that are difficult for the driver of the vehicle 12100 to visually recognize. Then, the microcomputer 12051 determines the collision risk, which indicates the risk of collision with each obstacle. In the case where the collision risk is equal to or higher than the set value and therefore there is a possibility of collision, the microcomputer 12051 outputs a warning to the driver via the audio speaker 12061 or the display portion 12062, and performs forced deceleration or evasive steering via the drive system control unit 12010. Therefore, the microcomputer 12051 can assist driving to avoid collisions.

[0195] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 may identify a pedestrian by determining whether there is a pedestrian in the imaging images of the imaging units 12101 to 12104. For example, the identification of a pedestrian is performed by extracting feature points in the imaging images of the imaging units 12101 to 12104 as infrared cameras and determining whether it is a pedestrian by performing pattern matching processing on a series of feature points representing the outline of the object. When the microcomputer 12051 determines that there is a pedestrian in the imaging images of the imaging units 12101 to 12104 and thus identifies the pedestrian, the sound / image output portion 12052 controls the display portion 12062 so that an emphasized square outline is displayed to be superimposed on the identified pedestrian. The sound / image output portion 12052 may also control the display portion 12062 so that an icon representing a pedestrian or the like is displayed at a desired position.

[0196] An example of a vehicle control system to which the technology according to the present disclosure can be applied has been described above. For example, the technology according to the present disclosure can be used in the vehicle exterior information detection unit 12030 among the above components. Specifically, in Figure 1 The distance measurement module 100 in the embodiment can be used in the vehicle exterior information detection unit 12030. By using the technology according to the present disclosure in the vehicle exterior information detection unit 12030, the leakage of the illumination light can be reduced and the distance measurement performance can be improved.

[0197] It should be noted that the above-mentioned embodiments show examples of embodying the present technical content, and the matters in the embodiments and the matters specifying the present invention in the claims have a corresponding relationship. Similarly, the matters specifying the present invention in the claims and the matters with the same names in the embodiments of the present technical content have a corresponding relationship. However, the present technical content is not limited to these embodiments, and can be embodied by applying various modifications to the embodiments without departing from the scope of the present technical content.

[0198] It should be noted that the beneficial effects described in this specification are merely examples and are not restrictive, and other beneficial effects may be provided.

[0199] Note that the present technical content may also have the following configurations.

[0200] (1) A ranging module, comprising:

[0201] A sensor chip, wherein a first pixel region and a second pixel region are arranged on a light receiving surface of the sensor chip, wherein the first pixel region is arranged with a plurality of first pixels receiving reflected light of irradiated light from a light source, and the second pixel region is located between the first pixel region and the light source and is arranged with second pixels;

[0202] a light shielding wall, the light shielding wall being disposed between the first pixel region and the second pixel region; and

[0203] A support substrate to which the sensor chip is connected, the support substrate being disposed between the light shielding wall and the sensor chip, the support substrate being formed with an opening for guiding the reflected light to the first pixel region and the second pixel region.

[0204] (2) The ranging module according to (1), wherein:

[0205] The opening includes a first opening and a second opening separated by a bridge portion that is a part of the support substrate,

[0206] The first opening is located directly above the first pixel region, and

[0207] The second opening is located directly above the second pixel region.

[0208] (3) The ranging module according to (2), wherein:

[0209] The light shielding wall is provided in the bridge portion, and

[0210] A width of the light shielding wall is smaller than a distance between the first pixel region and the second pixel region.

[0211] (4) The ranging module according to any one of (1) to (3), further comprising:

[0212] a laser chip having a plurality of laser diodes arranged as the light source; and

[0213] A driver chip is provided with laser diode drivers for driving the plurality of laser diodes respectively, wherein

[0214] The sensor chip is connected to a back surface of the support substrate opposite to a front surface which is a surface on a light receiving side.

[0215] (5) The ranging module according to (4), wherein:

[0216] The laser chip is disposed between the second pixel and the driver chip.

[0217] (6) The ranging module according to (5), wherein:

[0218] The laser chip and the driver chip are connected to the front surface of the support substrate.

[0219] (7) The ranging module according to (5), wherein:

[0220] The laser chip and the driver chip are connected to the back side of the support substrate, and

[0221] The openings further include a third opening that guides the irradiation light from the laser chip.

[0222] (8) The ranging module according to (5), wherein:

[0223] The laser chip is connected to the back side of the support substrate,

[0224] The driver chip is connected to the front side of the support substrate, and

[0225] The openings further include a third opening that guides the irradiation light from the laser chip.

[0226] (9) The ranging module according to (4), wherein:

[0227] The laser chip is stacked on the driver chip.

[0228] (10) The ranging module according to (9), wherein:

[0229] The laser chip is connected to the front surface of the support substrate through wires.

[0230] (11) The ranging module according to (9), wherein:

[0231] The driver chip is connected to the back surface of the support substrate through solder balls.

[0232] (12) The ranging module according to (9), wherein:

[0233] The laser chip is connected to the back side of the support substrate, and

[0234] The openings further include a third opening that guides the irradiation light from the laser chip.

[0235] (13) The ranging module according to any one of (1) to (12), further comprising

[0236] A ranging processing unit, wherein

[0237] The second pixel comprises a reference pixel, and

[0238] The distance measurement processing unit calculates a distance based on a time from a time when light is received by the reference pixel to a time when light is received by the first pixel.

[0239] (14) The ranging module according to any one of (1) to (13), further comprising:

[0240] control circuit, where

[0241] The first pixel comprises a first photodiode,

[0242] The second pixel comprises a monitoring pixel,

[0243] The monitoring pixel includes a second photodiode and a sample-and-hold circuit, and

[0244] When the cathode potential of the second photodiode decreases when the monitoring pixel receives light, the higher the potential held by the sample and hold circuit is, the lower the potential provided by the control circuit to the anodes of the first photodiode and the second photodiode is.

[0245] Reference numerals

[0246] 100 Distance Measurement Module

[0247] 111, 112 lens

[0248] 120 Sealing member

[0249] 121 Blackout wall

[0250] 122 Optical Filters

[0251] 130 Support substrate

[0252] 139, 149, 159 wires

[0253] 140 Laser Chip

[0254] 141 Laser diode

[0255] 148 welding balls

[0256] 150 Driver Chip

[0257] 151 Laser Diode Driver

[0258] 200 sensor chips

[0259] 201 pixel chip

[0260] 202 Circuit Chip

[0261] 205 Solid-state imaging element

[0262] 209 Bump

[0263] 211, 212 Photoelectric conversion element

[0264] 220 pixel array unit

[0265] 221 Measuring pixel area

[0266] 222 reference pixel area

[0267] 230 measured pixels

[0268] 240 reference pixels

[0269] 250 signal processing units

[0270] 251 TDC

[0271] 252 Measurement Processing Unit

[0272] 311, 381 pMOS transistors

[0273] 320 Timing Detection Circuit

[0274] 330 Sample and hold circuit

[0275] 340, 350 Buffer

[0276] 382 Inverter

[0277] 401 Monitoring Pixel

[0278] 500 Control Unit

[0279] 510 pixel average acquisition unit

[0280] 511 Resistor

[0281] 512 Capacitor

[0282] 520 Time average acquisition unit

[0283] 521 Variable resistor

[0284] 522 variable capacitor

[0285] 530 Potential Control Unit

[0286] 531 Amplifier

[0287] 12030 External vehicle information detection unit

Claims

1. A ranging module, comprising: A sensor chip, wherein a first pixel region and a second pixel region are arranged on a light receiving surface of the sensor chip, wherein the first pixel region is arranged with a plurality of first pixels receiving reflected light of irradiated light from a light source, and the second pixel region is located between the first pixel region and the light source and is arranged with second pixels; a light shielding wall, wherein the light shielding wall is arranged between the first pixel region and the second pixel region; as well as A support substrate to which the sensor chip is connected, the support substrate being disposed between the light shielding wall and the sensor chip, the support substrate being formed with an opening for guiding the reflected light to the first pixel region and the second pixel region.

2. The ranging module according to claim 1, wherein: The opening includes a first opening and a second opening separated by a bridge portion that is a part of the support substrate, The first opening is located directly above the first pixel region, and The second opening is located directly above the second pixel region.

3. The distance measurement module according to claim 2, wherein: The light shielding wall is provided in the bridge portion, and A width of the light shielding wall is smaller than a distance between the first pixel region and the second pixel region.

4. The ranging module according to claim 1, further comprising: A laser chip, wherein the laser chip is provided with a plurality of laser diodes as the light source; as well as A driver chip is provided with laser diode drivers for driving the plurality of laser diodes respectively, wherein The sensor chip is connected to a back surface of the support substrate opposite to a front surface which is a surface on a light receiving side.

5. The distance measurement module according to claim 4, wherein: The laser chip is disposed between the second pixel and the driver chip.

6. The distance measurement module according to claim 5, wherein: The laser chip and the driver chip are connected to the front surface of the support substrate.

7. The distance measurement module according to claim 5, wherein: The laser chip and the driver chip are connected to the back side of the support substrate, and The openings further include a third opening that guides the irradiation light from the laser chip.

8. The distance measurement module according to claim 5, wherein: The laser chip is connected to the back side of the support substrate, The driver chip is connected to the front side of the support substrate, and The openings further include a third opening that guides the irradiation light from the laser chip.

9. The distance measurement module according to claim 4, wherein: The laser chip is stacked on the driver chip.

10. The distance measurement module according to claim 9, wherein: The laser chip is connected to the front surface of the support substrate through wires.

11. The distance measurement module according to claim 9, wherein: The driver chip is connected to the back surface of the support substrate through solder balls.

12. The distance measurement module according to claim 9, wherein: The laser chip is connected to the back side of the support substrate, and The openings further include a third opening that guides the irradiation light from the laser chip.

13. The ranging module according to claim 1, further comprising: A ranging processing unit, wherein The second pixel comprises a reference pixel, and The distance measurement processing unit calculates a distance based on a time from a time when light is received by the reference pixel to a time when light is received by the first pixel.

14. The ranging module according to claim 1, further comprising: control circuit, where The first pixel comprises a first photodiode, The second pixel comprises a monitoring pixel, The monitoring pixel includes a second photodiode and a sample-and-hold circuit, and When the cathode potential of the second photodiode decreases when the monitoring pixel receives light, the higher the potential held by the sample and hold circuit is, the lower the potential provided by the control circuit to the anodes of the first photodiode and the second photodiode is.

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