CN214954068U - Transmitting module and electronic equipment - Google Patents

Abstract

The utility model relates to a range finding and 3D formation of image field disclose a transmission module and electronic equipment. A transmit module, comprising: the optical signal processing device comprises an emitter, an astigmatic element and a diffractive optical element, wherein the astigmatic element is arranged on a light path of the emitter and used for performing astigmatic deformation on the light signal emitted by the emitter, and the diffractive optical element is arranged on the light path of the emitter and is positioned on one side of the astigmatic element, which is far away from the emitter. The astigmatic deformation transmitting module is used for projecting the optical signal transmitted by the transmitter into the speckle shape on the target object through the astigmatic element, and distance conversion is carried out according to the speckle shape, so that the calculation method is simple, the distance can be obtained without shooting pictures for many times, and the delay time is reduced; meanwhile, the projection of the speckles can reduce the background light interference depth distance calculation and improve the accuracy. Meanwhile, the receiving module has lower cost and mass production.

Description

Transmitting module and electronic equipment

Technical Field

The utility model relates to a range finding and 3D imaging technology field, in particular to transmission module and electronic equipment.

Background

TOF is an abbreviation of Time of Flight (TOF) technology, i.e. a sensor emits modulated near-infrared light, which is reflected after encountering an object, and the sensor converts the distance of the photographed scene by calculating the Time difference or phase difference between light emission and reflection to generate depth information. In general, TOF technology mainly includes iToF and dtofs, where: the iToF (induced time of flight) is a method for indirectly measuring time, most indirect measurement schemes adopt a method for measuring phase offset, that is, a phase difference between a transmitted sine wave and a received sine wave, and a flight time t, that is, a distance Z is a function of the phase difference, so that Z can be solved, and therefore the iToF needs to perform distance calculation in a post-processing manner, and two-step or multi-step phase reduction exists, so that the frame number (Hz) cannot be increased, and the iToF background light is easy to interfere with depth distance calculation to generate misjudgment. dToF (direct time of flight) is a direct measurement of time of flight. ToF was originally intended to measure time directly to distance, but measurement systems that achieved ps resolution were slow to mature, i.e., SPAD. SPAD (single photon avalanche diode), a single photon avalanche diode, is a device which can generate response current in ps-level time, and the working principle is that a reverse bias photodiode is adopted to make the diode work in a very small voltage range which exceeds breakdown voltage but is not broken down, and the diode is in a very sensitive working range, so that the diode can be triggered to generate avalanche current only by weak optical signals, and the corresponding speed is very fast and the price is expensive.

Therefore, it is an urgent technical problem to be solved by those skilled in the art to develop a module capable of accurately calculating a distance and saving cost.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a transmission module and electronic equipment for the accuracy carries out the distance calculation, and the cost is practiced thrift.

In order to achieve the above purpose, the utility model provides the following technical scheme:

in a first aspect, the present invention provides a transmitting module, including: the optical signal processing device comprises an emitter, an astigmatic element and a diffractive optical element, wherein the astigmatic element is arranged on a light path of the emitter and is used for performing astigmatic deformation on the optical signal emitted by the emitter, and the diffractive optical element is arranged on the light path of the emitter and is positioned on one side of the astigmatic element, which is far away from the emitter.

The emitter may in particular be a laser. The utility model discloses a laser instrument transmission laser, laser form a small amount of speckles through the astigmatism component, and a small amount of speckles form a large amount of speckles via the diffraction of diffraction optical device and throw target object. Compare in the iToF through the method of surveying phase deviation and the method of dToF direct measurement flight time, the utility model discloses an astigmatism component carries out the astigmatic deformation with the light signal of transmitter transmission and launches the speckle shape that the module throws on the target object to carry out the distance conversion according to the speckle shape, calculation method is simple, need not to shoot the photo many times and can try to get the distance, reduces delay time; meanwhile, the projection of the speckles can reduce the background light interference depth distance calculation and improve the accuracy.

Optionally, the astigmatic element is an astigmatic lens;

the astigmatic lens has a first focal length along a first direction and a second focal length along a second direction, and the first focal length is not equal to the second focal length; wherein the first direction is perpendicular to the second direction.

The first and second directions perpendicular to each other may be specifically x and y directions, and the x direction of the astigmatic lens has a first focal length f_xThe y direction has a second focal length f_yAnd f is_xIs not equal to f_y. Because the curvature radius of the astigmatic lens xy direction is different, the focal length is different, and the speckle shapes are different under different distances, so that the distance can be calibrated according to the speckle shapes.

Optionally, the astigmatic lens has a radius of curvature of 2mm to 3mm, for example 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3mm, of a surface of the astigmatic lens facing the emitter; and/or the presence of a gas in the gas,

the radius of curvature of the surface of the astigmatic lens facing away from the emitter is 2mm to 3mm, for example 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3 mm.

Optionally, the astigmatic lens satisfies the following conditional expression:

wherein:

f is the focal length of the lens;

n is the refractive index of the lens material;

n_mis the refractive index of the substance surrounding the lens material;

R₁is the radius of curvature of the surface of the lens on the side close to the light source;

R₂is the radius of curvature of the surface of the lens remote from this side;

d is the thickness of the lens.

The astigmatic lens can be formed by modifying a cylindrical lens, specifically, a radius R of the cylindrical lens in the x direction₁Grinding the lens in the y-direction to a radius R₁' circular arc, R₁' specifically 2mm to 3 mm.

In a second aspect, the present invention further provides an electronic device, including a receiving module and the transmitting module as described above;

the receiving module is arranged on the periphery of the transmitting module and used for receiving speckles projected to a target object by the transmitting module, determining characteristic information of the speckles and acquiring distance information of the target object according to the characteristic information.

The transmitting module in the electronic device performs astigmatic deformation on the laser signal of the laser through the astigmatic element, so that the receiving module needs to receive speckles projected to a target object, determine characteristic information of the speckles, and calibrate and measure the distance of the target object according to the characteristic information. The receiving module may be a charge coupled device. The Charge Coupled Device (CCD) has low cost, so that the cost of the whole module is reduced, and the module has mass production.

Optionally, the characteristic information includes an ellipse ratio of the speckle shape.

The distance can be judged by identifying the shape of the speckle on the CCD. Specifically, the speckle shape may use ellipse ratios as an index, i.e., each ellipse ratio corresponds to a different distance, so that the ellipse ratio by analyzing the speckle corresponds to a specific distance value.

In a third aspect, the present invention further provides a distance measuring method, including:

projecting speckles emitted by the emission module onto a target object;

and determining the characteristic information of speckles on the target object, and acquiring the distance information of the target object according to the characteristic information.

The conversion method for converting the distance according to the speckle shape is recorded in the memory of the CCD. The laser emits laser towards the astigmatic element, the laser forms a small amount of speckles through the astigmatic element, the small amount of speckles are diffracted by the diffractive optical device to form a large amount of speckles to be projected to a target object, and then the speckles are received by the CCD; the CCD processes the speckle shape and converts the speckle shape into distance according to a conversion method stored in a memory. The conversion method is simple and easy to implement.

Optionally, the determining the characteristic information of the speckles on the target object and acquiring the distance information of the target object according to the characteristic information includes:

and acquiring the size ratio of the speckles in two mutually perpendicular directions, and converting the distance according to the size ratio.

The two mutually perpendicular directions can be specifically the x direction and the y direction, and the x in the speckle shape is recorded in the CCD memory_n，y_nBy conversion between the ratio of (a) and the distance, e.g. the ratio y₁/x₁＝1m，y₅/x₅5 m. Thus formed by x_n、y_nThe ratio, distance, can be calculated for each speckle.

Optionally, before determining the characteristic information of the speckles on the target object and acquiring the distance information of the target object according to the characteristic information, the method further includes:

the speckle shapes of the target object and the diffraction optical device at different distances are obtained, and the distance is calibrated according to the speckle shapes.

The distinguishing distance correction method firstly moves the target object by different distances to record the shapes of scattered spots, thereby establishing the corresponding relation between the distance values and the shapes of the scattered spots, namely calibrating the distance according to the shapes of the scattered spots.

Optionally, the acquiring the speckle shapes of the target object and the diffractive optical element at different distances, and calibrating the distance according to the speckle shapes includes:

and acquiring the dimension ratio of the speckles in two mutually perpendicular directions, and calibrating the distance according to the dimension ratio.

The judgment distance correction method may specifically be: firstly, moving the target object by different distances to record the shape of a scattered spot, and then recording x in the shape of the scattered spot_n，y_nOf (d), e.g. of y₁/x₁＝1m，y₅/x₅5 m. The distance conversion method can be recorded in a CCD memory. Thus formed by x_n、y_nThe ratio, distance, can be calculated for each speckle.

Drawings

Fig. 1 is a schematic structural diagram of an electronic device according to an embodiment of the present invention;

FIGS. 2a-2d are schematic diagrams illustrating the fabrication of an astigmatic lens;

FIGS. 3a-3c are schematic diagrams of speckle projection distance and shape change;

FIG. 4 is a schematic diagram of the distribution of speckle shapes on a CCD;

FIG. 5 is a schematic diagram of a single speckle pattern of FIG. 4 on a CCD;

fig. 6 is a flowchart of a distance measuring method according to an embodiment of the present invention.

Icon: 1-a transmitter; 2-an astigmatic element; 3-diffractive optics; 4-a charge coupled device; 5-target object.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

The embodiment of the utility model provides a transmission module includes transmitter, astigmatism component and diffraction optical device, and the astigmatism component sets up in the light path of transmitter and is used for carrying out the astigmatism with the light signal of transmitter transmission and warp, and the diffraction optical device sets up in the light path of transmitter, and is located one side that the astigmatism component deviates from the transmitter.

Compare in the iToF through the method of surveying phase deviation and the method of dToF direct measurement flight time, the utility model discloses an astigmatism component carries out the astigmatic deformation with the light signal of transmitter transmission and launches the speckle shape that the module throws on the target object to carry out the distance conversion according to the speckle shape, calculation method is simple, need not to shoot the photo many times and can try to get the distance, reduces delay time; meanwhile, the projection of the speckles can reduce the background light interference depth distance calculation and improve the accuracy.

As shown in fig. 1, an embodiment of the present invention provides an electronic device, including: the transmitting module comprises a transmitter 1, an astigmatic element 2 and a diffractive optical element 3, wherein the astigmatic element 2 is arranged on a light path of the transmitter 1 and is used for performing astigmatic deformation on an optical signal transmitted by the transmitter 1, and the diffractive optical element 3 is arranged on the light path of the transmitter 1 and is positioned on one side of the astigmatic element 2, which is far away from the transmitter 1; the receiving module is arranged on the periphery of the transmitting module and used for receiving speckles projected to the target object 5 by the transmitting module, determining characteristic information of the speckles and acquiring distance information of the target object according to the characteristic information.

Compare in the method that iToF passes through surveying phase deviation, the embodiment of the utility model provides a receive the speckle shape that the transmission module throwed on target object 5 through receiving module to carry out distance conversion according to the speckle shape, calculation method is simple, need not to shoot the photo many times and can try to get the distance, reduces delay time; meanwhile, the projection of the speckles can reduce the background light interference depth distance calculation and improve the accuracy. Compare in dToF needs expensive SPAD, the embodiment of the utility model provides an in lower, have the volume production nature of receiving module cost.

Optionally, the emitter 1 is a laser.

In one possible implementation, referring to fig. 1, laser light is emitted by a laser, the laser light forms a small amount of speckles through the astigmatic element 2, and the small amount of speckles are diffracted by the diffractive optical device 3 to form a large amount of speckles to be projected to the target object 5 so as to be received by the receiving module.

Optionally, the astigmatic element 2 is an astigmatic lens; the astigmatic lens has a first focal length along a first direction and a second focal length along a second direction, and the first focal length is not equal to the second focal length; wherein the first direction is perpendicular to the second direction.

The first and second directions perpendicular to each other may be specifically x and y directions, and the x direction of the astigmatic lens has a first focal length f_xThe y direction has a second focal length f_yAnd f is_xIs not equal to f_y. Because the curvature radius of the astigmatic lens xy direction is different, the focal length is different, and the speckle shapes are different under different distances, so that the distance can be calibrated according to the speckle shapes.

In one possible implementation, as shown in fig. 2a-2d, the astigmatic lens can be modified from a cylindrical lens (as shown in fig. 2 a), specifically, a cylindrical lens with a radius R in the x-direction₁From 3mm to 5mm, for example 3mm, 3.5mm, 4mm, 4.5mm or 5 mm; grinding the lens in the y-direction to form a lens with a radius R₁' arc (as shown in FIG. 2 b), R₁' in particular 2mm to 3mm, for example 2mm, 2.5mm or 3 mm. The finished astigmatic lens is shown in fig. 2c and 2 d. The focal length of the astigmatic lens satisfies the following conditionsFormula (II):

wherein:

f is the focal length of the lens;

n is the refractive index of the lens material;

n_mis the refractive index of a substance, such as air, surrounding the lens material;

R₁is the radius of curvature of the surface of the lens on the side close to the light source;

R₂is the radius of curvature of the surface of the lens remote from this side;

d is the thickness of the lens (the distance between two faces of the lens along the optical axis).

Optionally, the radius of curvature R of the surface of the astigmatic lens facing the emitter 1 side₁From 2mm to 3mm, for example 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3 mm; and/or the radius of curvature R of the surface of the astigmatic lens facing away from the emitter 1₂From 2mm to 3mm, for example 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3 mm.

Optionally, the receiving module is a charge coupled device 4. CCD (charge coupled device) is a charge coupled device, is a detecting element which uses charge to represent signal size and uses coupling mode to transmit signal, and has the advantages of self-scanning, wide sensing spectrum range, small distortion, small size, light weight, low system noise, small power consumption, long service life, high reliability and the like, and can be made into a combined piece with very high integration level. The CCD image sensor can directly convert an optical signal into an analog current signal, and the current signal is amplified and subjected to analog-to-digital conversion to realize acquisition, storage, transmission, processing and reproduction of an image. The remarkable characteristics are as follows: 1. the volume is small and the weight is light; 2. the power consumption is small, the working voltage is low, the shock resistance and the vibration resistance are realized, the performance is stable, and the service life is long; 3. the sensitivity is high, the noise is low, and the dynamic range is large; 4. the response speed is high, the self-scanning function is realized, the image distortion is small, and no afterimage exists; 5. the super-large-scale integrated circuit is produced by applying a super-large-scale integrated circuit process technology, the pixel integration level is high, the size is accurate, and the commercial production cost is low. Thus, the present embodiment uses the CCD device as a receiving module. The cost of CCD is lower, thus reduce the cost of the whole module, make it have the mass production nature.

Optionally, the characteristic information includes an ellipse ratio of the speckle shape.

The distance can be distinguished by distinguishing the shape of the speckle on the charge coupled device. Specifically, the speckle shape may use ellipse ratios as an index, i.e., each ellipse ratio corresponds to a different distance, so that the ellipse ratio by analyzing the speckle corresponds to a specific distance value.

Before the electronic device is used, the distance is calibrated, and as shown in fig. 3a, 3b and 3c, the target object 5 is moved by different distances (as shown in D in fig. 3 a)₁D in FIG. 3b₂And D in FIG. 3c₃) And recording the shape of the scattered spots so as to establish the corresponding relation between the distance value and the speckle shape, namely calibrating the distance according to the speckle shape. Specifically, referring to fig. 4 and 5, the x in the speckle shape is recorded_n，y_nIs compared to the corresponding distance D_nA relationship of, e.g. y₁/x₁＝1m，y₅/x₅5 m. After the distance is calibrated, the electronic equipment can be used for measuring the distance so as to ensure the accuracy of measurement.

Therefore, the electronic equipment can obtain the distance without taking pictures for many times, and the delay time is reduced; the projection of the speckles can reduce the interference depth distance calculation of the background light and improve the accuracy; only general charge coupled devices are needed, the cost is low, and the mass production is realized.

In a second aspect, as shown in fig. 6, an embodiment of the present invention further provides a distance measuring method, including the following steps:

s601, projecting speckles emitted by the emission module onto a target object;

s602, obtaining speckle shapes of the target object and the diffractive optical device at different distances, and calibrating the distance according to the speckle shapes;

s603, determining the characteristic information of speckles on the target object, and acquiring the distance information of the target object according to the characteristic information.

Referring to fig. 3a, 3b and 3c, the target object is first moved by different distances (see D in fig. 3 a)₁D in FIG. 3b₂And D in FIG. 3c₃) And recording the shape of the scattered spots so as to establish the corresponding relation between the distance value and the speckle shape, namely calibrating the distance according to the speckle shape. The conversion method for converting the distance according to the speckle shape is recorded in the memory of the CCD. The laser emits laser towards the astigmatic element, the laser forms a small amount of speckles through the astigmatic element, the small amount of speckles are diffracted by the diffractive optical device to form a large amount of speckles to be projected to a target object, and then the speckles are received by the CCD; the CCD processes the speckle shape and converts the speckle shape into distance according to a conversion method stored in a memory. The conversion method is simple and easy to implement.

Optionally, the S602 specifically includes: and acquiring the dimension ratio of the speckles in two mutually perpendicular directions, and calibrating the distance according to the dimension ratio. The S603 specifically includes: and acquiring the dimension ratio of the speckles in two mutually perpendicular directions, and converting the distance according to the dimension ratio.

The distance can be judged by identifying the shape of the speckle on the CCD. Specifically, the speckle shape may use ellipse ratios as an index, i.e., each ellipse ratio corresponds to a different distance, so that the ellipse ratio by analyzing the speckle corresponds to a specific distance value.

In a possible implementation manner, the method for determining distance correction specifically may be: firstly, moving the target object by different distances to record the shape of a scattered spot, and then recording x in the shape of the scattered spot_n，y_nOf (d), e.g. of y₁/x₁＝1m，y₅/x₅5 m. The distance conversion method can be recorded in a CCD memory. Thus formed by x_n、y_nThe ratio, distance, can be calculated for each speckle.

It will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments of the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (6)

1. A transmitter module, comprising: the optical signal processing device comprises an emitter, an astigmatic element and a diffractive optical element, wherein the astigmatic element is arranged on a light path of the emitter and is used for performing astigmatic deformation on the optical signal emitted by the emitter, and the diffractive optical element is arranged on the light path of the emitter and is positioned on one side of the astigmatic element, which is far away from the emitter.

2. The transmit module of claim 1, wherein the astigmatic element is an astigmatic lens;

the astigmatic lens has a first focal length along a first direction and a second focal length along a second direction, and the first focal length is not equal to the second focal length; wherein the first direction is perpendicular to the second direction.

3. The transmit module of claim 2, wherein the focal length of the astigmatic lens satisfies the following conditional expression:

wherein f is the focal length of the lens; n is the refractive index of the lens material; n is_mIs the refractive index of the substance surrounding the lens material; r₁Is the radius of curvature of the surface of the lens on the side close to the light source; r₂Is the radius of curvature of the surface of the lens remote from this side; d is the thickness of the lens.

4. The transmit module of claim 2, wherein the astigmatic lens has a radius of curvature of 2mm to 3mm on a surface facing the transmitter; and/or the presence of a gas in the gas,

the curvature radius of the surface of one side, which is far away from the emitter, of the astigmatic lens is 2mm-3 mm.

5. An electronic device comprising a receiving module and a transmitting module according to any one of claims 1-4;

the receiving module is arranged on the periphery of the transmitting module and used for receiving speckles projected to a target object by the transmitting module, determining characteristic information of the speckles and acquiring distance information of the target object according to the characteristic information.

6. The electronic device of claim 5, wherein the feature information comprises an ellipse ratio of the speckle shape.

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