CN215599370U

CN215599370U - Time-of-flight camera module and electronic equipment

Info

Publication number: CN215599370U
Application number: CN202121128301.4U
Authority: CN
Inventors: 曾媛媛; 阎小霞
Original assignee: Shenzhen Goodix Technology Co Ltd
Current assignee: Shenzhen Goodix Technology Co Ltd
Priority date: 2021-05-21
Filing date: 2021-05-21
Publication date: 2022-01-21
Anticipated expiration: 2031-05-21
Also published as: WO2022242225A1

Abstract

The embodiment of the application provides a TOF module and electronic equipment of making a video recording, can effectively improve the optical axis skew between transmission module and the receiving module with lower cost. This TOF module of making a video recording includes: the circuit board comprises an upper surface and a lower surface, wherein the upper surface at least comprises a first area and a second area which are not overlapped with each other; the emitter chip is arranged in the first area through the ceramic substrate, and the projection area of the ceramic substrate on the upper surface of the circuit board is smaller than the area of the upper surface; the first lens base is fixed on the ceramic substrate, and the emitter chip is accommodated in the first lens base; the optical device is fixed in the first lens seat and arranged above the emitter chip; an image sensor chip disposed in the second region; the second lens base is fixed on the upper surface of the circuit board, and the image sensor chip is accommodated in the second lens base; and the imaging lens is fixed in the second lens base and is arranged above the image sensor chip.

Description

Time-of-flight camera module and electronic equipment

Technical Field

The application relates to the technical field of electronic products, in particular to a flight time camera shooting module and electronic equipment for ranging or 3D measurement.

Background

The Time of Flight (TOF) camera module is a common depth camera module, and can be used for measuring depth of field (depth) or distance information, and can realize a three-dimensional imaging or distance detection function of an electronic device on a target object. The TOF camera module generally includes an optical signal transmitting (Tx) module and an optical signal receiving (Rx) module.

At present, the emitting module of common TOF on the market generally adopts area light source TOF (flood TOF), but the area light source is limited by luminous power and heat dissipation problem, and emergent light intensity can not accomplish highly to influence the effective distance and the detection precision that TOF detected. In order to improve the detection distance and accuracy, the use of point light sources tof (spot tof) is being attempted in the industry. However, after the light signal of the light source in the Spot TOF reaches the target object through the optical element and returns to the light receiving unit such as a Complementary Metal-Oxide-Semiconductor (CMOS) sensor, the effective number of the Spot irradiation points and the number of pixels of the sensor are generally greatly different (the pixels of the sensor are generally over one hundred thousand pixels), so that the number of the pixels of the sensor capable of detecting the Spot returned by the target object is much smaller than that of the Flood TOF, which is limited by the chip area and the process of the emitting unit, and the number of the speckles is limited, so in the Spot TOF scheme, it is desirable that each speckle point can be effectively detected at the sensor end, which results in the TOF module being particularly sensitive to the optical axis offset angle between the emitting module and the receiving module, if there is an offset between the optical axis of the emitting module and the optical axis of the receiving module, part of speckles of the transmitting module cannot reach the sensor after being reflected by the target object, so that three-dimensional imaging or distance detection of the target object can be influenced. In order to solve the problem, a solution idea is to rotate the optical axis of the transmitting module and the optical axis of the receiving module which are installed on the support plate, and to align the optical axis of the transmitting module and the optical axis of the receiving module with each other by correcting the deviation angle of the optical axis through the rotating module. However, the rotation angles of the optical axis of the transmitting module and the optical axis of the receiving module are affected by various factors, and the correction effect on the optical axis deviation by rotating the modules is limited, so that the imaging function or the distance detection function of the TOF camera module is affected.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a TOF module and electronic equipment of making a video recording, can effectively improve the optical axis skew between transmission module and the receiving module with lower cost.

In a first aspect, a TOF camera module is provided, which includes: a circuit board including an upper surface and a lower surface, the upper surface including at least a first region and a second region that do not overlap each other; the emitter chip is arranged in the first area through a ceramic substrate and used for emitting optical signals to a target object, wherein the projection area of the ceramic substrate on the upper surface of the circuit board is smaller than the area of the upper surface; the first lens base is fixed on the ceramic substrate, and the emitter chip is accommodated in the first lens base; the optical device is fixed in the first lens base and arranged above the emitter chip, and an optical signal emitted by the emitter chip forms a speckle optical signal after passing through the optical device; the image sensor chip is arranged in a second area of the upper surface of the circuit board, and is used for receiving a depth optical signal returned after the speckle optical signal irradiates the target object and converting the depth optical signal into an electric signal; the second lens base is fixed on the upper surface of the circuit board, and the image sensor chip is accommodated in the second lens base; and the imaging lens is fixed in the second lens base, arranged above the image sensor chip and used for imaging the depth light signal to the image sensor chip.

Above-mentioned technical scheme, a circuit board of transmitter chip and image sensor chip sharing, transmitter chip and image sensor chip can refer to common benchmark (mark point) or refer to each other like this when setting up on the circuit board, are favorable to reducing the counterpoint tolerance between transmitter chip and the image sensor chip to can reduce the optical axis of transmission module and the relative optical axis contained angle of receiving the module greatly, promote the formation of image function or the distance detection function of TOF camera module. Secondly can reduce the cost of circuit board, once more, the transmission module no longer need the metal support with receiving the module at the in-process of equipment, not only is favorable to reducing the support cost of TOF module of making a video recording to also need the equipment process flow of extra metal support between transmitter chip and the image sensor chip, also be favorable to reducing the equipment process cost of TOF module of making a video recording.

Further, the mirror seat is not shared to transmission module and receiving module, and transmission module and receiving module respective optical assembly are independent structure promptly, like this, if certain structure take place to damage only need change the damage the structure can, need not to change whole mirror seat, effectively reduced the cost of TOF module of making a video recording.

The emitter chip and the first lens base are arranged on the circuit board through the ceramic substrate, and the ceramic substrate is an insulator, so that the radiating performance is good, and the problem of thermoelectric separation of the emitting module can be solved through the ceramic substrate. In addition, only the emitter chip sets up on ceramic substrate, and the image sensor chip sets up on the lower circuit board of cost, is favorable to further reducing the cost of TOF module of making a video recording.

In some possible embodiments, a projected area of the ceramic substrate on the upper surface of the circuit board is less than 15% of an area of the upper surface.

In some possible embodiments, a projected area of the ceramic substrate on the upper surface of the circuit board is 9% of an area of the upper surface.

In some possible embodiments, the optical device includes a shaping lens, the shaping lens is a plastic collimator lens, and the shaping lens includes 3 lenses or 1 lens.

In some possible embodiments, the optical device further comprises: a diffractive optical element disposed above the shaping lens.

The configuration of the diffractive optical element is beneficial to spatial modulation of the shaping optical signal emitted by the shaping lens to form speckle optical signals of a plurality of areas, so that the measurement range of the TOF camera module is expanded, and the precision of three-dimensional imaging or distance detection is improved.

In some possible embodiments, the surface of the ceramic substrate is planar.

In some possible embodiments, the area of the first region is smaller than the area of the second region. Set up the area of first region into being less than the area of second region, also be exactly less with the size setting of ceramic substrate, because ceramic substrate's cost is higher, consequently can further reduce the manufacturing cost of TOF camera module with the less of size setting of ceramic substrate.

In some possible embodiments, the method further comprises: and the auxiliary device is arranged in a third area of the circuit board and used for assisting the emitter chip to generate the optical signal, wherein the third area is respectively not overlapped with the first area and the second area. The auxiliary device sets up at the lower circuit board of cost, has further reduced the cost of TOF module of making a video recording.

In some possible embodiments, the third area is located on an upper surface of the circuit board.

In some possible embodiments, a size of the first region and the third region in a first direction is larger than a size of the second region in the first direction, wherein the first direction is a direction perpendicular to a line connecting an optical axis center point of the image sensor chip and an optical axis center point of the emitter chip.

In some possible embodiments, at least a portion of the third area is located on a lower surface of the circuit board.

In some possible embodiments, the device further comprises a shielding case, and at least part of the auxiliary device is arranged in the shielding case.

In some possible embodiments, the shield has an opening through which a thermally conductive silicone grease is injected.

Above-mentioned technical scheme injects heat conduction silicone grease into the shield cover through the trompil in to heat conduction silicone grease can be fast with the heat conduction in the shield cover to the exterior space, realizes supplementary chip rapid cooling, has improved the radiating efficiency of TOF module of making a video recording.

In some possible embodiments, the method further comprises: and the heat dissipation device is arranged on the outer surface of the shielding case.

The heat dissipation device is arranged outside the shielding cover, so that heat is transmitted outwards through the heat conduction silicone grease and the heat dissipation device, and the heat dissipation speed is improved. Moreover, the small-area concentrated heat emitted by the driving chip passes through the heat-conducting silicone grease and then passes through the large-area heat dissipation device, so that the heat dissipation area can be further increased.

In some possible embodiments, the heat dissipation device includes a thermal pad and/or a heat sink copper sheet.

In some possible embodiments, the emitter chip is fixed on the ceramic substrate after the ceramic substrate is fixed on the first region of the circuit board.

In some possible embodiments, the circuit board is a flexible circuit board or a rigid-flex board or a printed circuit board.

In some possible embodiments, the emitter chip is fixed to the ceramic substrate by a die bonding process, and the image sensor chip is fixed to the second region by a die bonding process.

In a second aspect, an electronic device is provided, comprising: the TOF camera module is configured to measure depth information of a target object; and the control unit is used for carrying out operation control on at least one function of the electronic equipment according to the depth information.

Drawings

Fig. 1 is a schematic diagram of the offset between the optical axes of the transmit and receive modules.

Fig. 2 is a schematic diagram of the rotation of the optical axis of the transmit module and the optical axis of the receive module.

Fig. 3 is a schematic structural diagram of a TOF camera module according to an embodiment of the present application.

Fig. 4 is a schematic perspective view of a TOF camera module according to an embodiment of the present application.

Fig. 5 is a top view of the TOF camera module shown in fig. 4.

Fig. 6 is a main flow chart of a production process of the TOF camera module according to the embodiment of the application.

Fig. 7 is a schematic block diagram of an electronic device of an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

For any TOF camera module, the TOF camera module may include a TOF transmitting module (or referred to as a transmitting unit) and a TOF receiving module (or referred to as a receiving unit), wherein the TOF transmitting module is configured to transmit an optical signal, the optical signal is irradiated to a target object and then returns to the receiving module to generate a depth optical signal, and the target object may refer to an object to be photographed (or referred to as a photographing target, an imaging target, a detection target); the receiving module is used for receiving the depth optical signal, or the receiving module is used for sensing the returned optical signal, and the depth optical signal carries the depth information of the object to be shot, so that the imaging function or the distance measuring function of the target object can be realized.

TOF can be classified into Flood TOF and Spot TOF. The light source in the Flood TOF projects light signals reaching the target object through the optical element to form uniform surface light, and the light signals reaching the target object through the light source in the Spot TOF pass through the optical element to form speckle light signals, namely, arrays formed by a series of light spots or the arrays are called as Spot light. The technical scheme of the embodiment of the application is applied to the Spot TOF. In the Spot TOF, an optical signal emitted by a light source passes through an optical element to finally form a speckle light signal, and the speckle light signal is projected to a target object.

As before, the TOF module of making a video recording is more sensitive to the optical axis skew angle between transmission module and the receiving module, if there is the skew between the optical axis of transmission module and the optical axis of receiving module, has the alignment tolerance between the image sensor chip of the transmitter chip of transmission module and receiving module promptly, then can influence the degree of depth light signal that the receiving module received to influence electronic equipment to the imaging effect or the range finding effect of target object.

As shown in FIG. 1, the image sensor chip has a gamma with respect to the receiving circuit board₁The emitter chip has a gamma with respect to the circuit board at the emitting end₂The angle between the image sensor chip and the emitter chip is gamma₁+γ₂In other words, the optical axis offset angle between the transmitting module and the receiving module is γ. Assuming that the transmitting module transmits a high-frequency modulated narrow-pulse speckle optical signal to the target object, the speckle optical signal includes 64 × 9 — 576 spot lights, if the optical axis of the transmitting module is aligned with the optical axis of the receiving module, the receiving module may receive the 576 spot lights reflected by the target object, so that the receiving module may image or measure the distance of the target object based on the received 576 spot lights. However, the module structure shown in fig. 1 may cause a part of the speckle light to be lost, the receiving module may receive less than 576 speckle lights reflected by the target object, and the depth calculation performed by the receiving module on the target object based on the received part of the speckle light may cause a decrease in the accuracy of imaging or ranging.

A common TOF camera module usually contains independent transmission module and receiving module, a complete transmission module includes the transmitter chip, transmission end circuit board, transmission end optics etc, and receiving module includes the sensor chip, receiving terminal circuit board, receiving terminal optics etc, install on same metal support after two modules are assembled respectively, on the basis of this module structure, in order to guarantee that the optical axis between the receiving module that figure 1 shows and the transmission module does not have the skew, for having reduced the counterpoint tolerance between image sensor chip and the transmitter chip, can rotate the optical axis of transmission module and the optical axis of receiving module, so that the optical axis of transmission module aligns mutually with the optical axis of receiving module, can refer to figure 2 specifically. However, the rotation angle of the optical axis of the transmitting module and the optical axis of the receiving module may be affected by various factors, for example, the metal bracket for mounting the transmitting module and the receiving module or the internal space of the terminal electronic device may limit, so that the transmitting module and the receiving module may not be rotated to eliminate the optical axis offset, which may affect the imaging function or the distance measurement function of the TOF camera module.

In view of this, the embodiment of the present application provides a TOF camera module, which can effectively reduce the relative optical axis included angle between a transmitting module and a receiving module with a lower cost, so as to improve the imaging function or the distance measuring function of the TOF camera module.

The TOF camera module according to the embodiment of the present application will be described in detail below with reference to fig. 3 to 5.

It should be noted that, for convenience of description, like reference numerals denote like parts in the embodiments of the present application, and a detailed description of the like parts is omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width and other dimensions of the various components in the embodiments of the present application and the overall thickness, length, width and other dimensions of the integrated device shown in the drawings are only exemplary and should not constitute any limitation to the present application.

Fig. 3 is a schematic structural diagram of the TOF camera module 100 according to the embodiment of the present application. The TOF camera module 100 may include a circuit board 110, an emitter chip 120, an image sensor chip 130, a first mount 140, a second mount 150, optics 160, an imaging lens 170, and a ceramic substrate 180.

The circuit board 110 includes an upper surface and a lower surface, and the upper surface includes at least a first region and a second region that do not overlap each other. The emitter chip 120 is disposed on a first region of the circuit board through a ceramic substrate 180 for emitting an optical signal to a target object, and a projected area of the ceramic substrate 180 on an upper surface of the circuit board 110 is smaller than an area of the upper surface of the circuit board 110. The first lens holder 140 is fixed on the ceramic substrate 180, and the emitter chip 120 is accommodated in the first lens holder 140. The optical device 160 is fixed in the first lens holder 140 and disposed above the emitter chip 120, and the optical signal emitted by the emitter chip 120 forms a speckle optical signal after passing through the optical device 160.

The image sensor chip 130 is disposed on a second region of the upper surface of the circuit board 110, wherein the image sensor chip 130 is configured to receive a depth optical signal returned after the speckle optical signal is irradiated to the target object and is configured to convert the depth optical signal into an electrical signal. The second mirror base 150 is fixed on the circuit board 110, wherein the image sensor chip 130 is accommodated in the second mirror base 150. It should be noted that the holder of the embodiments of the present application may also be referred to as a holder or a holder. The imaging lens 170 is fixed in the second lens holder 150 and disposed above the image sensor chip 130, for imaging the depth light signal to the image sensor chip 130.

The circuit board 110 is electrically connected to the connector. In this way, the circuit board 110 can electrically connect the TOF camera module with an external circuit through the connector. Alternatively, the Circuit board 110 may be a Flexible Printed Circuit (FPC). Since the FPC is soft, as shown in fig. 4, when the circuit board 110 is an FPC, the TOF camera module 100 may further include a reinforcement member 111 to support the FPC. Wherein, the reinforcement 111 may be but not limited to steel sheet reinforcement. Of course, the Circuit Board 110 may also be a Printed Circuit Board (PCB) or a rigid-flex Board. Wherein, when circuit board 110 is the rigid-flex board, the module 100 is made a video recording to TOF also can include the reinforcement to improve the module 100's that makes a video recording flatness of TOF.

The surface of the ceramic substrate 180 is provided with a circuit for electrically connecting the emitter chip 120 with the circuit board 110. Illustratively, the ceramic substrate 180 is a flat plate, i.e. the surface of the ceramic substrate 180 is a plane, and the ceramic substrate 180 and the first mirror holder 150 are two independent structures. Wherein, the projected area of the ceramic substrate 180 on the upper surface of the circuit board 110 may be less than 15% of the area of the upper surface of the circuit board 110. For example, the projected area of the ceramic substrate 180 on the upper surface of the circuit board 110 is 9% of the area of the upper surface of the circuit board 110. Because the cost of the ceramic substrate is high, the projected area of the ceramic substrate on the upper surface of the circuit board 110 is only 9% of the area of the upper surface of the circuit board, and the cost of the TOF camera module can be further reduced.

Optionally, the first area is smaller than the second area, that is, the projected area of the ceramic substrate on the upper surface of the circuit board 110 is smaller than the projected area of the receiving module on the upper surface of the circuit board 110. Because the cost of ceramic substrate is higher, consequently can reduce the manufacturing cost of TOF camera module with the less of ceramic substrate size setting equally.

The emitter chip 120 may be a Vertical Cavity Surface Emitting Laser (VCSEL), a Light Emitting Diode (LED), or an array formed by combining a plurality of Light sources, and is used for Emitting Light signals. The optical signal may be an optically modulated, processed or controlled optical signal carrying a spatial optical pattern, an optically modulated, processed or controlled optical signal illuminated in different regions, an optically modulated, processed or controlled optical signal illuminated periodically, or a combination thereof. A VCSEL is a semiconductor diode laser, and the emitted laser beam generally exits the device from the top surface in a substantially vertical manner, and the VCSEL has many advantages of small size, large power, small beam divergence angle, stable operation, and the like. Specifically, the emitter chip 120 may be a VCSEL chip emitting light from a single chip at multiple points, where multiple light-emitting points are arranged in a two-dimensional matrix, and emit multiple laser signals correspondingly to form a matrix laser signal array.

In the embodiment of the present application, the ceramic substrate 180 may be disposed on the circuit board 110 first, and then the emitter chip 120 is disposed on the ceramic substrate 180. As an example, the ceramic substrate 180 may be Mounted on the circuit board 110 by Surface Mount Technology (SMT), and for example, the ceramic substrate 180 may be soldered to the circuit board 110 by providing a pad array on a lower Surface of the ceramic substrate 180 and by the pad array. Thereafter, the emitter chip 120 may be bonded to the ceramic substrate 180 through a Die Bond (DB) process.

The optical device 160 includes a shaping lens for performing optical path shaping on the optical signal emitted by the transmitter chip 120 to obtain a shaped optical signal, for example, converting the optical signal emitted by the VCSEL into a collimated optical signal. The shaping lens may be, for example, a collimator lens, a projection objective lens, or any optical element capable of achieving a beam shaping effect. The embodiment of the application takes the collimating mirror as an example. By configuring the collimating mirror, the diameter and the divergence angle of the light beam can be changed in the dimming system, so that the light beam is changed into a collimated parallel light beam, the energy of the light beam is more concentrated, and a fine high-power-density light spot can be obtained. Further, since the maximum number of signals emitted by the emitter chip 120 can be reached under the condition that the height of the emitting module is close to or even level with the height of the receiving module, and the optical characteristics of the collimating mirror determine that the collimating mirror has a certain aperture and thickness. Consequently, set up the plastic lens into the collimating lens, the module of making a video recording of TOF need not additionally to increase other structures and can make the height of transmission module and receive the highly being close of module, is favorable to reducing the cost of the module of making a video recording of TOF.

Wherein, the shaping lens may include 1 lens. At this time, the cost of the shaping lens can be minimized, so that the cost of the TOF camera module can be further reduced. Alternatively, the shaping lens may be formed of a plurality of lenses arranged in a lens group back and forth along the optical axis, and for example, the shaping lens may include a lens formed of 3 sheets of a common transparent material. The performance of the TOF camera module is better when the shaping lens comprises 3 lenses.

Optionally, the shape of the shaping lens may be a square or other shape, which is not specifically limited in this application.

Alternatively, the plastic lens may be a glass material or a plastic material. Considering that the plastic shaping lens is not resistant to high temperature and the thermal deformation temperature is about 120 ℃. Since the ceramic substrate 180 may be mounted to the circuit board 110 by the SMT process, the temperature required for the SMT process is generally over 200 degrees. The shaping lens is usually fixed in a lens holder by a barrel (barrel), and the barrel is usually made of Polycarbonate (PC), and the PC material is resistant to temperature of 200 degrees or less. If the shaping lens is fixed in the first lens holder 140 through the lens barrel, the first lens holder 140 is disposed on the ceramic substrate 180, and then the ceramic substrate 180 is disposed on the circuit board 110, the shaping lens and the lens holder may be damaged.

Therefore, in order to prevent the shaping lens and the lens holder from being damaged by high temperature, in the embodiment of the present application, the ceramic substrate 180 is first mounted on the circuit board 110, and after the emitter chip 120 is disposed on the ceramic substrate 180, the shaping lens is then accommodated in the first lens holder 140 through the lens barrel, and finally, the first lens holder 140 is disposed on the ceramic substrate 180, so that the shaping lens and the first lens holder 140 can be effectively protected.

The imaging lens 170 may include one lens or a lens group composed of a plurality of lenses, which are arranged in a lens group along the optical axis in a front-to-back manner, and image the depth light signal formed after being reflected and/or scattered from the target object to the image sensor chip 130. Optionally, the imaging lens 170 is made of plastic, but may be an optical lens made of other materials.

After the image sensor chip 130 is disposed on the circuit board 110, the imaging lens 170 is accommodated in the second lens holder 150.

Further, the optical device 160 may further include an optical filter located in the second lens holder 150 and disposed between the image sensor chip 130 and the imaging lens 170.

Further, the optical device 160 may further include an optical signal replication element fixed in the first mirror base 140 and disposed above the collimating mirror, for replicating the collimated optical signal to obtain the speckle optical signal. Alternatively, the Optical signal replication element may be at least one or a combination of Diffractive Optical Elements (DOE), Micro Lens Array (MLA), grating, or any other Optical element that can form spot light. The embodiments of the present application are described by taking DOE as an example. The DOE is usually made of glass or plastic, and is used for projecting the light beam emitted from the emitter chip 120 to a plurality of areas of speckle optical signals after being replicated by a certain multiple. The diffraction capability of the DOE determines the measurement range of the TOF camera module. This embodiment can carry out spatial modulation to speckle light signal through configuration light signal duplication of elements, has enlarged the measuring range of TOF module of making a video recording, has improved depth measurement's measurement accuracy.

By way of example and not limitation, if the emitter chip 120 can emit 20 light spots to form an optical signal, the optical signal is converted into a collimated optical signal through the collimating mirror, and if the optical signal replicating element is a 3 × 3 DOE, the light spots can be replicated by 3 × 3, and finally the speckle optical signal formed by 180 light spots is projected onto the target object.

It should be understood that the specific examples in the embodiments of the present application are for the purpose of promoting a better understanding of the embodiments of the present application and are not intended to limit the scope of the embodiments of the present application.

Optionally, as shown in fig. 4 and 5, the TOF camera module 100 may further include an auxiliary device 190 for assisting the emitter chip 120 in generating the optical signal. The auxiliary device 190 may include a driving chip for driving the emitter chip to emit light. In addition, the auxiliary device 190 may further include other elements, such as an inductor, a capacitor, a resistor, a boost converter (boost), and the like.

The auxiliary device 190 is disposed at a third region of the circuit board 110, which does not overlap with the first region and the second region, respectively. Referring again to fig. 4 and 5, the third region may be located on the upper surface of the circuit board 110. At this time, the sizes of the first and third regions in the first direction, which is a direction perpendicular to a line connecting an optical axis center point of the image sensor chip 130 and an optical axis center point (Baseline) of the emitter chip 120, may be larger than the size of the second region in the first direction.

Alternatively, at least a portion of the third region may be located on the lower surface of the circuit board 110. The third region located on the lower surface of the circuit board 110 may be located at any region of the lower surface of the circuit board 110, for example, a region opposite to the first region as shown in fig. 5, or a region opposite to the second region.

Through setting up at least part of the third region at the lower surface of circuit board, can save the space of the upper surface of circuit board, be favorable to reducing the circuit board size to further reduce the size of TOF camera module.

It should be understood that, in the embodiments of the present application, the terms "first", "second" and "third" are merely used to distinguish different objects, and do not limit the scope of the embodiments of the present application.

In order to shield electromagnetic interference generated by other external components, the TOF camera module 100 may further include a shielding case, wherein at least a portion of the auxiliary device 190 is disposed in the shielding case. For example, the driver chip and the boost device may be disposed within the shield can.

That is, the shield can shields only the heat in the third region without shielding the other region (e.g., the first region), which can reduce the size and production cost of the shield can. Further, since the shield can only shield the heat in the third region, the transmitting module and the shield can are two independent components and are located in different regions of the circuit board, and the problem that whether the lens and the lens holder in the transmitting module are damaged by high temperature or not is not considered when the shield can is mounted on the circuit board 110 by the SMT process. In this case, the installation sequence of the shielding case and the transmitting module is not particularly limited in the embodiments of the present application. For example, the shielding cover may be attached to the circuit board 110 before the ceramic substrate 180 is attached, or the shielding cover may be mounted on the circuit board 110 after the whole transmitting module is attached to the circuit board 110 through the ceramic substrate 180.

After the shielding case is arranged, the shielding case may affect heat dissipation of components in the shielding case. For example, the driving chip is arranged in the shielding case, the heat of the driving chip is concentrated, and the driving chip is small and cannot be directly added with a radiator. Based on this, the shield can optionally be provided with an opening through which the thermally conductive silicone grease is injected. For example, the heat conductive silicone grease may be injected from an opening of the shield case by a needle, and the inner space of the shield case or a part of the space of the shield case is filled by using the flow property of the silicone grease, for example, the introduced silicone grease may be filled between the driver chip and the shield case.

Wherein the opening may be located at the top or at the side wall of the shield can. The size and shape of the opening can be set according to the practical application, and the embodiment of the present application is not particularly limited to this.

Above-mentioned technical scheme injects heat conduction silicone grease into the shield cover through the trompil in to heat conduction silicone grease can be fast with the heat conduction exterior space in the shield cover, has realized the rapid cooling of the components and parts in the shield cover, has improved the radiating efficiency of TOF camera module.

In order to further improve the heat dissipation efficiency, a heat dissipation device may be disposed outside the shield case, for example, a heat dissipation device may be disposed on an outer surface of the shield case. For example, the heat spreader device may include a thermal pad and/or a heat spreader copper sheet. Therefore, the heat dissipation device is arranged outside the shielding cover, so that heat is transmitted outwards through the heat conduction silicone grease and the heat dissipation device, and the heat dissipation speed is improved. Moreover, the small-area concentrated heat emitted by the driving chip passes through the heat-conducting silicone grease and then passes through the large-area heat dissipation device, so that the heat dissipation area can be further increased.

The structure of the TOF camera module 100 is described in detail above, and a manufacturing process flow of the TOF camera module 100 will be described below with reference to fig. 6.

As shown in fig. 6, the receiving module adopts a conventional focusing process, and the transmitting module adopts an Automatic Alignment (AA) process.

The ceramic substrate 180 is first attached to the circuit board 110 by the SMT process, and specifically, as described above, the ceramic substrate 180 may be soldered to the circuit board 110 by providing a pad array on the lower surface of the ceramic substrate 180 and by using the pad array.

Then, the emitter chip 120 is bonded to the ceramic substrate 180 through the DB process, and the image sensor chip 130 is also bonded to the circuit board 110 through the DB process. When the emitter chip 120 and the image sensor chip 130 are both bonded to the circuit board 110 by the DB process, the emitter chip 120 and the image sensor chip 130 may be bonded with reference to a common mark point, which can greatly reduce the alignment tolerance of the emitter chip 120 and the image sensor chip 130, thereby reducing the rotation angle of the optical axis.

Alternatively, the emitter chip 120 and the image sensor chip 130 may be referenced to each other. For example, the image sensor chip 130 is attached to the circuit board 110 with reference to the attachment position of the emitter chip 120, which also reduces the alignment tolerance between the emitter chip 120 and the image sensor chip 130.

Next, the transmitter chip 120 is electrically connected to the ceramic substrate 180 through a Wire Bond (WB) process using a Wire bonding apparatus. For example, the pads on the emitter chip 120 and the pads on the ceramic substrate 180 are connected by gold wires. Also, the image sensor chip 130 is electrically connected to the circuit board 110 through the WB process.

The imaging lens 170 is pre-locked, and the imaging lens 170 is fixed in the second lens holder 150 through the lens barrel. Alternatively, the filter may be fixed in the second lens holder 150 before the imaging lens 170 is fixed in the second lens holder 150.

Then, a Holder Mount (HM) and a focusing step are performed, that is, the pre-locking assembly obtained in the previous step (i.e., the second lens Holder 150 with the imaging lens 170 mounted thereon) is disposed on the circuit board 110, and the imaging lens 170 is adjusted to a fixed position near the optimal imaging position by a screw thread between the imaging lens 170 and the second lens Holder 150, that is, the imaging lens 170 is adjusted to a fixed height.

The optics 160 are then mounted within the first mount 140. Specifically, the DOE may be assembled in the first mount 140 with the reshaping lens after the reshaping lens is mounted in the first mount 140, and then the first mount 140 with the DOE and the reshaping lens mounted thereon is mounted on the ceramic substrate 180.

Finally, the optics 160 and the emitter chip 120 are adjusted by the AA process so that the optics 160 and the emitter chip 120 are aligned to ensure that the optical signals emitted by the emitter chip 120 can all form speckle optical signals after passing through the optics 160.

During the adjustment of the optical device 160 and the emitter chip 120 by the AA process, the image may also be acquired by the image sensor chip 130 in real time to optimize the AA process. Specifically, when the optics 160 and the emitter chip 120 are adjusted by the AA process, the image sensor chip 130 may collect the depth light signals in real time to determine whether the field of view of the emitter module matches the field of view of the receiver module, i.e., whether all the depth light signals are collected by the image sensor chip 130 is determined by the number of the collected effective spot lights. If all depth light signals are collected by the image sensor chip 130, it can be determined that the optics 160 and the emitter chip 120 are adjusted to the optimal position. If the image sensor chip 130 does not collect all depth light signals, it may be determined that the optics 160 and the emitter chip 120 have not been adjusted to the optimal positions, and the AA process continues to be used to adjust the optics 160 and the emitter chip 120.

This application embodiment, a circuit board is shared to transmitter chip and image sensor chip, and set up on the same surface of this circuit board, transmitter chip and image sensor chip are when setting up on the circuit board like this, can refer to common mark point or refer to each other, be favorable to reducing the counterpoint tolerance between transmitter chip and the image sensor chip, thereby can reduce the optical axis of transmission module and the rotation angle of the optical axis of receiving the module greatly, promote the imaging function or the distance detection function of TOF camera module. Secondly for transmitter chip and image sensor chip set up the scheme on the circuit board of difference respectively, the TOF module of making a video recording of this application embodiment only includes a circuit board, can reduce the cost of circuit board material and process, once more, the in-process of transmission module and receiving module at the equipment no longer needs the metal support, not only be favorable to reducing the support cost of TOF module of making a video recording, and also need not extra metal support's equipment process flow between transmitter chip and the image sensor chip, also be favorable to reducing the equipment process cost of TOF module of making a video recording.

In addition, the emitter chip and the first lens base are arranged on the circuit board through the ceramic substrate, and the ceramic substrate is an insulator, so that the radiating performance is good, and the problem of thermoelectric separation of the emitting module can be solved through the ceramic substrate. In addition, only the emitter chip sets up on ceramic substrate, and the image sensor chip sets up on the lower circuit board of cost, is favorable to further reducing the cost of TOF module of making a video recording. In general, the heat dissipation of the transmitting module and the overall cost of the module can be considered.

The embodiment of the present application further provides an electronic device, as shown in fig. 7, the electronic device 200 may include a TOF camera module 210 and a control unit 220.

The TOF camera module 210 may be the TOF camera module 100 in the foregoing embodiment, and is configured to measure depth information of a target object, and the control unit 220 may receive the depth information to perform operation control on at least one function of the electronic device 200, for example, may perform distance-based shooting auxiliary focusing according to the measured depth information of a human face, or unlock the electronic device according to the depth information, and so on.

By way of example and not limitation, the electronic device in the embodiments of the present application may include a device capable of implementing a complete or partial function, such as a smart phone, a smart watch, or smart glasses; the device can also comprise devices which are only concentrated on a certain type of application function and need to be matched with other devices such as a smart phone and the like for use, such as various smart bracelets for physical sign monitoring, smart jewelry and the like.

It should be noted that, without conflict, the embodiments and/or technical features in the embodiments described in the present application may be arbitrarily combined with each other, and the technical solutions obtained after the combination also fall within the protection scope of the present application.

It is to be understood that the terminology used in the embodiments of the present application and the appended claims is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the present application. For example, as used in the examples of this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Those of ordinary skill in the art will appreciate that the elements of the examples described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described above generally in terms of their functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed system and apparatus may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially or partially contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a time of flight TOF module of making a video recording which characterized in that includes:

a circuit board including an upper surface and a lower surface, the upper surface including at least a first region and a second region that do not overlap each other;

the emitter chip is arranged in the first area through a ceramic substrate and used for emitting optical signals to a target object, wherein the projection area of the ceramic substrate on the upper surface of the circuit board is smaller than the area of the upper surface;

the first lens base is fixed on the ceramic substrate, and the emitter chip is accommodated in the first lens base;

the optical device is fixed in the first lens base and arranged above the emitter chip, and an optical signal emitted by the emitter chip forms a speckle optical signal after passing through the optical device;

the image sensor chip is arranged in a second area of the upper surface of the circuit board, and is used for receiving a depth optical signal returned after the speckle optical signal irradiates the target object and converting the depth optical signal into an electric signal;

the second lens base is fixed on the upper surface of the circuit board, and the image sensor chip is accommodated in the second lens base;

and the imaging lens is fixed in the second lens base, arranged above the image sensor chip and used for imaging the depth light signal to the image sensor chip.

2. The TOF camera module of claim 1 wherein a projected area of the ceramic substrate on the upper surface of the circuit board is less than 15% of an area of the upper surface.

3. The TOF camera module of claim 2 wherein the projected area of the ceramic substrate on the upper surface of the circuit board is 9% of the area of the upper surface.

4. The TOF camera module of any of claims 1 to 3, wherein the optical device comprises a shaping lens, wherein the shaping lens is a plastic collimator lens, and wherein the shaping lens comprises 3 lenses or 1 lens.

5. The TOF camera module of claim 4, wherein the optics further comprise:

a diffractive optical element disposed above the shaping lens.

6. A TOF camera module according to any of claims 1 to 3 wherein the surface of the ceramic substrate is planar.

7. The TOF camera module of any of claims 1 to 3, wherein the area of the first region is smaller than the area of the second region.

8. The TOF camera module of any of claims 1 to 3, further comprising:

and the auxiliary device is arranged in a third area of the circuit board and used for assisting the emitter chip to generate the optical signal, wherein the third area is respectively not overlapped with the first area and the second area.

9. The TOF camera module of claim 8, wherein the third region is located on an upper surface of the circuit board.

10. The TOF camera module of claim 9, wherein a dimension of the first region and the third region in a first direction is larger than a dimension of the second region in the first direction, wherein the first direction is a direction perpendicular to a line connecting an optical axis center point of the image sensor chip and an optical axis center point of the emitter chip.

11. The TOF camera module of claim 8, wherein at least a portion of the third region is located on a lower surface of the circuit board.

12. The TOF camera module of claim 8 further comprising a shield, at least a portion of the auxiliary device being disposed within the shield.

13. The TOF camera module of claim 12 wherein the shield has an aperture through which thermally conductive silicone grease is injected.

14. The TOF camera module of claim 12, further comprising:

and the heat dissipation device is arranged on the outer surface of the shielding case.

15. The TOF camera module of claim 14 wherein the heat dissipating device comprises a thermal pad and/or a heat dissipating copper sheet.

16. The TOF camera module of any of claims 1 to 3, wherein the emitter chip is fixed to the ceramic substrate after the ceramic substrate is fixed to the first region of the circuit board.

17. The TOF camera module of any of claims 1 to 3, wherein the circuit board is a flexible circuit board or a rigid-flex board or a printed circuit board.

18. The TOF camera module of any of claims 1 to 3, wherein the emitter chip is secured to the ceramic substrate by a die attach process and the image sensor chip is secured to the second region by a die attach process.

19. An electronic device, comprising:

the TOF camera module of any one of claims 1 to 18, for measuring depth information of a target object;

and the control unit is used for carrying out operation control on at least one function of the electronic equipment according to the depth information.