CN111366906A

CN111366906A - Projection apparatus and segmented TOF apparatus, manufacturing method thereof, and electronic apparatus

Info

Publication number: CN111366906A
Application number: CN202010426643.8A
Authority: CN
Inventors: 黄河; 孟玉凰; 楼歆晔; 林涛
Original assignee: Shanghai North Ocean Photonics Technology Co Ltd
Current assignee: Shanghai North Ocean Photonics Technology Co Ltd
Priority date: 2020-02-01
Filing date: 2020-05-19
Publication date: 2020-07-03
Also published as: CN111458692A; CN111458692B; CN111458693A

Abstract

A projection apparatus and a segmented TOF apparatus, a manufacturing method thereof, and an electronic apparatus. The segmented TOF apparatus comprises: a projection device, wherein the projection device comprises: a light source unit, wherein the light source unit comprises at least two light source partitions, and the at least two light source partitions are used for being lightened according to a certain time sequence to transmit light signals in a partition manner; and a diffractive optical element, wherein the diffractive optical element is correspondingly arranged on the light-emitting paths of the at least two light source subareas of the light source unit, and is used for performing diffraction processing on the light signal emitted by each light source subarea to form a subarea projection light field and projecting the subarea projection light field to a target view field; and a receiving device, wherein the receiving device is configured to receive the reflected optical signal from the target field of view in a time-sharing manner, so as to determine the depth information of the target field of view by measuring the flight time of the optical signal.

Description

Projection apparatus and segmented TOF apparatus, manufacturing method thereof, and electronic apparatus

Technical Field

The present invention relates to the field of TOF technologies, and in particular, to a projection apparatus and a segmented TOF apparatus, and a method of manufacturing the same, and an electronic device.

Background

Currently, in the mainstream scheme of the three-dimensional sensing technology, the TOF (time of flight) technology is widely concerned and applied in industries such as smart phones and the like by virtue of the advantages of small size, low error, direct output of depth data, strong interference resistance and the like. From the technical implementation, TOF has two types: one is direct ranging TOF (dTOF for short), i.e. determining distance by emitting, receiving light, and measuring photon time of flight; the other is the well-established indirect ranging tof (ietf) in the market, i.e. the distance is determined by converting the time of flight by measuring the phase difference between the transmitted and received waveforms. The direct distance measurement method is characterized in that the light is transmitted after being subjected to high-frequency modulation, the pulse repetition frequency is very high, the pulse width can reach ns to ps magnitude, very high single pulse energy can be obtained in a very short time, the signal to noise ratio can be increased while the low power consumption of a power supply is kept, a relatively long detection distance can be realized, the influence of ambient light on the distance measurement precision is reduced, and the requirements on the sensitivity and the signal to noise ratio of a detection device are lowered. In addition, the high frequency and narrow pulse width characteristics of the direct ranging TOF enable the average energy of the TOF to be small, and eye safety can be guaranteed.

However, the detection distance of the existing direct ranging TOF is proportional to power consumption, that is, the longer the detection distance of the direct ranging TOF is, the higher the required power consumption is, so that the existing direct ranging TOF has to be configured with a light source with higher power in order to realize detection at a longer distance to meet the needs of application scenarios such as VR/AR, and the existing direct ranging TOF often performs short-distance and long-distance detection under the condition of higher power consumption, thereby causing resource waste and affecting the application and popularization of the TOF technology.

Disclosure of Invention

An advantage of the present invention is to provide a projection apparatus and a segmented TOF apparatus, a method of manufacturing the same, and an electronic device, which can realize detection at a longer distance with lower power consumption, contributing to an enlargement of a detection range of TOF.

Another advantage of the present invention is to provide a projection apparatus and a segmented TOF apparatus, a method of manufacturing the same and an electronic device thereof, wherein in an embodiment of the invention, the segmented TOF apparatus is capable of dividing a target field of view into specific field of view segment arrangements for detecting different field of view segments at different times, so as to detect only a smaller field of view at the same time, which helps to reduce the power consumption required for long-range detection.

Another advantage of the present invention is to provide a projection apparatus and a sectional TOF apparatus, a method for manufacturing the same, and an electronic device, wherein in an embodiment of the present invention, the sectional TOF apparatus can illuminate corresponding field sections at different times by performing specific light source sectional arrangement on VCSEL light sources and lighting each light source section according to a certain time sequence, so as to achieve detection of different field sections at different times.

Another advantage of the present invention is to provide a projection apparatus and a sectional TOF apparatus, a method for manufacturing the same, and an electronic device, wherein in an embodiment of the present invention, the sectional TOF apparatus can use a Diffractive Optical Element (DOE) to diffract the emission beam of each light source section so as to project the light beam into any desired shape and distribution.

Another advantage of the present invention is to provide a projection apparatus and a segmented TOF apparatus, a method for manufacturing the same, and an electronic device, wherein, in an embodiment of the present invention, the DOE of the segmented TOF apparatus can be designed to be segmented or not segmented according to the segmented situation of the light source, which is helpful for meeting the requirements of different applications.

Another advantage of the present invention is to provide a projection apparatus and a segmented TOF apparatus, a manufacturing method thereof and an electronic device thereof, wherein, in an embodiment of the present invention, a light beam emitted by a light source segment of the segmented TOF apparatus can be collimated and then diffracted by the DOE, so as to achieve higher diffraction efficiency and improve the detection quality of the segmented TOF.

It is a further advantage of the present invention to provide a projection apparatus and a segmented TOF apparatus, a method of manufacturing the same and an electronic device, wherein in an embodiment of the invention, the DOE of the segmented TOF apparatus can arbitrarily control the distribution and shape of the projection light field to accommodate any desired field-of-view segmented arrangement.

Another advantage of the present invention is to provide a projection apparatus and a segmented TOF apparatus, a manufacturing method thereof and an electronic device thereof, wherein in an embodiment of the present invention, the DOE of the segmented TOF apparatus can perform a copy splicing on a viewing angle to form a larger viewing angle, which helps to meet a requirement of a larger target viewing field.

Another advantage of the present invention is to provide a projection apparatus and a segmented TOF apparatus, a method of manufacturing the same, and an electronic device, wherein in order to achieve the above advantages, no complex structures and large amounts of computation are required, and the requirements on software and hardware are low. Therefore, the present invention successfully and effectively provides a solution not only to provide a projection apparatus and a segmented TOF apparatus and a manufacturing method thereof and an electronic apparatus, but also to increase the practicality and reliability of the projection apparatus and the segmented TOF apparatus and the manufacturing method thereof and the electronic apparatus.

To achieve at least one of the above advantages or other advantages and objects, the present invention provides a zone TOF apparatus, including:

a projection device, wherein the projection device comprises:

a light source unit, wherein the light source unit comprises at least two light source partitions, and the at least two light source partitions are used for being lightened according to a certain time sequence to transmit light signals in a partition manner; and

a diffractive optical element, wherein the diffractive optical element is correspondingly arranged on the light-emitting paths of the at least two light source subareas of the light source unit, and is used for performing diffraction processing on the light signals emitted by each light source subarea to form a subarea projected light field and project the subarea projected light field to a target field of view; and

a receiving device, wherein the receiving device is configured to receive the reflected optical signal from the target field of view in a time-sharing manner, so as to determine the depth information of the target field of view by measuring the flight time of the optical signal.

In an embodiment of the invention, the at least two light source partitions are adapted to correspond to at least two field partitions of the target field one to one, and an area of each field partition is smaller than an area of the target field.

In an embodiment of the present invention, the surface micro-nano structure of the diffractive optical element is designed according to the field division of the target field, so that the projected light field formed by diffraction of the diffractive optical element matches with the field division.

In an embodiment of the invention, the light source unit is a VCSEL light source.

In an embodiment of the present invention, the diffractive optical element is provided with at least two diffractive zones, and the diffractive zones of the diffractive optical element are in one-to-one correspondence with the light source zones of the light source unit, and are configured to perform a diffraction process on optical signals emitted via the corresponding light source zones.

In an embodiment of the present invention, a spacing between adjacent ones of the light source sections is greater than a product of a mounting distance of the diffractive optical element and a tangent of a divergence half-angle of an optical signal emitted via the light source sections.

In an embodiment of the invention, the diffractive optical element is provided with only one diffractive region, and the diffractive regions correspond to all the light source zones for time-divisionally diffracting the optical signals emitted via the different light source zones.

In an embodiment of the invention, each of the light source partitions has a rectangular, circular or elliptical shape.

In an embodiment of the present invention, a shape of an area where the optical signal emitted through the light source division is incident on the surface of the diffractive optical element is kept in conformity with a shape of the light source division.

In an embodiment of the invention, the projection apparatus further includes a collimating unit, wherein the collimating unit is disposed between the light source unit and the diffractive optical element, and the collimating unit is configured to collimate the optical signal emitted by the light source partition of the light source unit to form a collimated optical signal, so that the diffractive optical element performs a diffraction process on the collimated optical signal.

In an embodiment of the invention, the collimating unit is a collimating lens.

In an embodiment of the invention, a shape of an area where the optical signal collimated by the collimating unit is incident on the surface of the diffractive optical element is an ellipse.

In an embodiment of the invention, the diffractive optical element is further configured to perform a copy splicing on the optical signals emitted through the light source partitions to form a larger field angle.

According to another aspect of the present invention, the present invention further provides a method of manufacturing a segmented TOF device, comprising the steps of:

arranging a light source unit, wherein the light source unit comprises at least two light source partitions, and the at least two light source partitions are used for being lightened according to a certain time sequence so as to emit light signals in a partition mode;

correspondingly arranging a diffractive optical element on the light emitting paths of the at least two light source subareas of the light source unit, wherein the diffractive optical element is used for performing diffraction processing on the light signals emitted by each light source subarea to form a subarea projected light field and project the subarea projected light field to a target field of view; and

and a receiving device is arranged, wherein the receiving device is used for receiving the optical signals reflected from the target field of view in a time-sharing manner so as to determine the depth information of the target field of view by measuring the flight time of the optical signals.

In an embodiment of the present invention, the method for manufacturing a segmented TOF apparatus further includes:

and arranging a collimation unit between the light source unit and the diffractive optical element, wherein the collimation unit is used for collimating the optical signal emitted by the light source partition of the light source unit to form a collimated optical signal, so that the diffractive optical element diffracts the collimated optical signal.

According to another aspect of the present invention, there is further provided a projection device comprising:

and the diffractive optical element is correspondingly arranged on the light emitting paths of the at least two light source subareas of the light source unit and is used for performing diffraction processing on the light signals emitted by each light source subarea to form a subarea projected light field and project the subarea projected light field to a target field of view.

According to another aspect of the present invention, the present invention further provides an electronic device comprising:

an electronic device body; and

at least one section TOF device, wherein the section TOF device is configured on the electronic equipment body and is used for detecting a target field of view through the section TOF device; wherein the segmented TOF apparatus comprises:

a projection device, wherein the projection device comprises:

a diffractive optical element, wherein the diffractive optical element is correspondingly arranged on the light-emitting paths of the at least two light source subareas of the light source unit, and is used for performing diffraction processing on the light signals emitted by each light source subarea to form a subarea projected light field and project the subarea projected light field to the target field of view; and

Further objects and advantages of the invention will be fully apparent from the ensuing description and drawings.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the claims.

Drawings

Fig. 1 is a block schematic diagram of a segmented TOF apparatus according to a first embodiment of the invention.

Fig. 2 shows a schematic configuration of a projection apparatus in the segmented TOF apparatus according to the first embodiment of the present invention.

Fig. 3 shows a schematic distribution diagram of the optical signal area of the segmented TOF device according to the above first embodiment of the invention at the surface of a diffractive optical element.

Fig. 4 shows a block schematic diagram of a segmented TOF device according to a second embodiment of the invention.

Fig. 5A shows a schematic configuration of a projection apparatus in the segmented TOF apparatus according to the second embodiment of the present invention.

Fig. 5B shows a schematic distribution diagram of the optical signal region of the segmented TOF apparatus according to the above-described second embodiment of the invention at the surface of the diffractive optical element.

Fig. 5C shows a schematic diagram of the distribution of the projected light field of the segmented TOF device according to the second embodiment of the invention described above.

Fig. 6A and 6B respectively show a schematic diagram of the deformation distribution of the projected light field of the segmented TOF device according to the second embodiment of the invention described above.

Fig. 7A to 7C show a variant of the projection device of the segmented TOF device according to the first embodiment of the invention described above.

Fig. 8A and 8B show a variant implementation of the projection device of the segmented TOF device according to the second embodiment of the invention described above.

FIG. 9 shows a flow diagram of a method of manufacturing a zoned TOF apparatus according to an embodiment of the present disclosure.

Fig. 10 is a schematic structural diagram of an electronic device according to an embodiment of the invention.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.

In the present invention, the terms "a" and "an" in the claims and the description should be understood as meaning "one or more", that is, one element may be one in number in one embodiment, and the element may be more than one in number in another embodiment. The terms "a" and "an" should not be construed as limiting the number unless the number of such elements is explicitly recited as one in the present disclosure, but rather the terms "a" and "an" should not be construed as being limited to only one of the number.

In the description of the present invention, it is to be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Referring to figures 1 to 3 of the drawings, a segmented TOF apparatus in accordance with a first embodiment of the invention is illustrated. Specifically, as shown in fig. 1, the segmented TOF apparatus 1 includes a projection apparatus 10 and a reception apparatus 20, and the projection apparatus 10 includes a light source unit 11 and a diffractive optical element 12. The light source unit 11 includes at least two light source partitions 111, and the at least two light source partitions 111 are lit up at a timing to divisionally emit light signals. The diffractive optical element 12 is correspondingly disposed in the light emitting paths of the at least two light source partitions 111 of the light source unit 11, and is configured to perform a diffraction process on the light signal emitted through each light source partition 111 to form a partitioned projected light field and project the partitioned projected light field to a target field of view. The receiving device 20 is configured to receive the reflected optical signal from the target field of view in time division, so as to determine the depth information of the target field of view by measuring the flight time of the optical signal, thereby detecting the whole target field of view.

In particular, the entire target field of view may be formed by at least two field of view segments, and the area of each field of view segment is smaller than the entire target field of view; at the same time, the at least two light source partitions 111 of the light source unit 11 of the projection apparatus 10 of the partitioned TOF apparatus 1 are controlled to emit light signals according to a certain time sequence, and form partitioned projected light fields after diffraction processing by the diffractive optical element 12 to project to the corresponding field partitions in the target field, so that the light source unit 11 only needs to illuminate different field partitions at different times so as to detect different field partitions at different times, and therefore, compared with the existing way of detecting the whole target field simultaneously by the direct ranging TOF, the partitioned TOF apparatus 1 of the present invention can detect the whole target field with lower power consumption, which not only makes the partitioned TOF apparatus 1 have obvious application potential in the field of consumer electronics, and can be used in a smart phone, acquiring real three-dimensional information in an external long-distance range, realizing multiple AR-level applications and creating a new selling point; but also in VR/AR to meet the ever-increasing demand for motion capture and recognition. Furthermore, in addition to the consumer electronics field, the segmented TOF apparatus 1 may also support various functions, including gesture sensing or proximity detection of various innovative user interfaces, such as in the fields of computers, home appliances and industrial automation, service robots, unmanned planes, internet of things, etc., with broad application prospects.

It should be noted that the diffractive optical element 12 of the present invention utilizes the diffraction characteristics of optical waves to diffract the incident light with a specific wavelength to achieve a desired projected light field (i.e., output light spot). In other words, the diffractive optical element 12 adjusts the energy and phase of the incident light through its surface micro-nano structure, so as to project the incident light into any desired shape and distribution (i.e. any desired projected light field). In other words, no matter what shape of field partition the target field of view is divided into, the sectional TOF apparatus 1 of the present invention can project the projected light field matching the field partition through the surface micro-nano structure design of the diffractive optical element 12, so as to completely detect the entire target field of view.

It will be appreciated that the target field of view may be evenly divided into N equal-area segments of the field of view, such that the power consumption required by the segmented TOF apparatus 1 to accomplish the same range detection is only a factor N times the existing power consumption; in other words, the sectional TOF apparatus 1 of the present invention may have a detection distance N times longer than the existing distance when consuming the same power consumption, that is, the sectional TOF apparatus 1 of the present invention can realize longer-distance detection with lower power consumption, which is helpful to expand the detection range of TOF.

It is worth mentioning that the light source unit 11 of the sectional TOF module 1 of the present invention may be, but is not limited to, implemented as a VCSEL (vertical-cavity surface-emitting laser) light source for emitting a laser-like light signal. Specifically, the VCSEL light source includes at least two VCSEL light source sections, and the point light sources in each VCSEL light source section can be simultaneously lit, while the point light sources in different VCSEL light source sections can be time-divisionally lit, so as to reduce the power consumption of the section TOF apparatus 1.

Preferably, the diffractive optical element 12 of the present invention can be designed in a partitioned or non-partitioned scheme according to different partitioning conditions of the VCSEL light source. For example, as shown in fig. 2, when the interval between the adjacent VCSEL light source partitions is large, that is, the light signals emitted by the adjacent light source partitions 111 do not overlap each other on the surface of the diffractive optical element 12, or the overlapping amount is extremely small, the diffractive optical element 12 may be designed in a partitioned scheme, that is, the diffractive optical element 12 may be provided with at least two diffractive partitions 121, and the diffractive partitions 121 are in one-to-one correspondence with the light source partitions 111 and used for performing diffraction processing on the light signals emitted by the corresponding light source partitions 111. When the interval between adjacent VCSEL light source partitions is small, that is, the overlapping area of the light signals emitted by the adjacent light source partitions 111 on the surface of the diffractive optical element 12 is large, the diffractive optical element 12 may be designed in a non-partitioned scheme, that is, the diffractive light source element 12 includes only one diffractive region, and the diffractive regions simultaneously correspond to all the light source partitions 111, and are used for performing diffraction processing on the light signals emitted by all the light source partitions 111.

More preferably, when the adjacent light source sections 111 are spaced apart by more than the product of the installation distance of the diffractive optical element 12 and the tangent value of the divergence half-angle of the optical signal emitted via the light source sections 111, the diffractive optical element 12 is designed in a section manner; when the distance between adjacent light source segments 111 is smaller than the product of the installation distance of the diffractive optical element 12 and the tangent of the divergence half-angle of the optical signal, the diffractive optical element 2 is designed in a non-segmented manner so as to prevent the optical signal emitted through one light source segment 111 from being diffracted by two or more diffractive segments at the same time.

For example, as shown in fig. 2, the light source unit 11 of the projection device 10 includes 2 × 2 light source sub-regions 111 (V1, V2, V3, V4, respectively), wherein the installation distance L of the diffractive optical element 12 is the distance between the diffractive optical element 12 and the light source unit 11, and the sub-region interval between the adjacent light source sub-regions 111 and the divergence half-angle of the light source sub-region 111 are defined as D and α, respectively, and if D > L tan (α), the diffractive optical element 12 is designed in a sub-region manner to include 2 × 2 diffraction sub-regions 121 (D1, D2, D3, D4, respectively).

In other words, when the distance between the adjacent light source partitions 111 is greater than the product of the installation distance of the diffractive optical element 12 and the tangent value of the divergence half angle of the optical signal, the optical signals emitted by different light source partitions 111 will not overlap on the surface of the diffractive optical element 12, so the diffractive optical element 12 is suitable for partition design at this time to meet different requirements of the optical signals of different light source partitions 111 on diffraction effect, thereby improving the diffraction quality of the partitions.

Illustratively, the shape of each of the light source partitions 111 of the light source unit 11 of the present invention may be implemented in, but is not limited to, a regular shape such as a rectangle (including a square and a rectangle), a circle, an ellipse, and the like, and may also be implemented in other irregular shapes. It is understood that the shape of the area where the light signal emitted via the light source partition 111 is incident on the surface of the diffractive optical element 12 generally conforms to the shape of the light source partition 111. For example, four circular regions as shown in fig. 3 are regions where light signals emitted from four light source segments 111 are incident on the surface of the diffractive optical element 12, respectively, and since the amount of overlap of the four circular regions is small, the diffractive optical element 12 may be designed in segments to include four diffractive segments 121 (D1, D2, D3, D4, respectively) corresponding thereto.

It is worth mentioning that the VCSEL light source is typically a divergent light source, that is, the VCSEL light source emits a light signal with a certain divergence angle, which will result in a decrease of the diffraction efficiency of the diffractive optical element 12. In order to improve the diffraction efficiency of the diffractive optical element 12, as shown in fig. 4, compared to the above first embodiment according to the present invention, the projection apparatus 10 of the segmented TOF apparatus 1 according to the second embodiment of the present invention may further include a collimation unit 13, wherein the collimation unit 13 is disposed between the light source unit 11 and the diffractive optical element 12, and is configured to collimate the optical signal emitted by the light source segment 111 of the light source unit 11 to form a collimated optical signal, so that the diffractive optical element 12 performs a diffraction process on the collimated optical signal to improve the diffraction efficiency of the diffractive optical element 12.

In other words, although the optical signal emitted by the VCSEL light source has a certain divergence angle, the divergence angle of the optical signal collimated by the collimating unit 13 becomes smaller, so that the efficiency of the diffractive optical element 12 diffracting the collimated optical signal with a smaller divergence angle becomes higher, and the zonal dodging effect can be better achieved. It is understood that, as shown in fig. 5A, the collimating unit 13 may be, but is not limited to being, implemented as a collimating lens 131 such as a spherical lens, an aspherical lens, a fresnel lens, a DOE beam shaper, and the like.

In particular, as long as the light signals emitted via the light source sections 111 do not overlap or have a small overlapping area when they are incident on the surface of the diffractive optical element 12 after being collimated by the collimating unit 13, the diffractive optical element 12 can still be provided with different diffractive sections 121 to correspond to the light source sections 111 in a matching manner.

For example, as shown in fig. 5A, the optical signals emitted by the four VCSEL light source sub-sections V1, V2, V3, and V4 with circular shapes in the projection device 10 are collimated by the collimating lens 131 and then incident on the surface of the diffractive optical element 12 to be diffracted by the corresponding diffractive sub-section 121 in the diffractive optical element 12. At this time, the area where the optical signal collimated by the collimating lens 131 is incident on the surface of the diffractive optical element 12 may be an elliptical area as shown in fig. 5B. Since the overlapping area between the four elliptical regions is small, the diffractive optical element 12 in this example of the present invention may still be provided with four diffractive divisions D1, D2, D3, D4 to correspond to the four elliptical regions, respectively. Furthermore, since the diffractive optical element 12 can modulate the incident light into an arbitrary outgoing light field distribution (i.e. the distribution of the projection light field), the four diffractive partial areas D1, D2, D3, D4 of the diffractive optical element 12 can each control the corresponding outgoing light field. For example, as shown in fig. 5C, the optical signal emitted via the VCSEL light source partition V1 exits the projected light field T1 through the diffractive partition D1; the optical signal emitted via the VCSEL light source partition V2 exits the projected light field T2 through the diffractive partition D2; the optical signal emitted via the VCSEL light source partition V3 exits the projected light field T3 through the diffractive partition D3; the optical signal emitted via the VCSEL light source partition V4 exits the projected light field T4 through the diffractive partition D4. In particular, in this example of the invention, the projected light fields T1, T2, T3, T4 correspond one-to-one to the VCSEL light source partitions V1, V2, V3, V4, and the distribution of the projected light fields T1, T2, T3, T4 is identical to the distribution of the VCSEL light source partitions V1, V2, V3, V4.

It is noted that the distribution of the light signal emitted via the VCSEL light source partition V1 out of the projected light field T1 through the diffractive partition D1 does not necessarily coincide with the distribution of the light source partition V1, precisely because the diffractive optical element 12 can arbitrarily control the shape and the positional distribution of the projected light field. In other words, the projected light field T1 need not be located at a position corresponding to the upper left corner, but may be located at a position corresponding to the upper right corner; even the four projected lightfields T1, T2, T3, T4 are not arranged 2 × 2, but in any desired arrangement, such as an arrangement of 1 × 4 (as shown in fig. 6A), or in more complex patterns, such as a trapezoidal arrangement (as shown in fig. 6B).

It is worth mentioning that when the distance between the adjacent light source subareas 111 is smaller than the product of the installation distance of the diffractive optical element 12 and the tangent value of the divergence half-angle of the optical signal, the optical signals emitted by the different light source subareas 111 will partially overlap on the surface of the diffractive optical element 12, and thus the diffractive optical element 12 is now adapted to a non-subarea design to ensure the diffractive effect of the diffractive optical element 12.

As shown in fig. 7A, the light source unit 11 of the projection device 10 of the present invention includes 1 to 4 VCSEL light source partitions V1, V2, V3 and V4, wherein the installation distance L of the diffractive optical element 12 is the distance between the diffractive optical element 12 and the light source unit 11, and the partition interval between the adjacent light source partitions 111 and the divergence half angle of the light source partition 111 are defined as d and α, respectively, it is easy to see that d < L tan (α), then the diffractive optical element 12 is designed in a non-partitioned manner, only one diffractive region is provided, and the diffractive regions simultaneously correspond to all the light source partitions 111, for diffracting the light signals emitted via the different light source partitions 111 in time, for example, as shown in fig. 7B, when the light signals emitted from the four VCSEL light source partitions V1, V2, V3 and V4 form an elliptical shape on the surface of the diffractive optical element 12, and the diffractive optical element 12 is not arranged in a larger diffractive region than the diffractive region having an elliptical shape of the light field, and the diffractive optical element 12 is arranged in a larger incident light field than the diffractive region.

It should be noted that when the diffractive optical element 12 is designed in a non-zoned manner, the diffractive optical element 12 can no longer individually form the required projected light field by means of different zones, but must satisfy the illumination requirements of different zones of the field of view by means of an overall distortion correction. For example, when the four incident light fields incident on the surface of the diffractive optical element have the deformed shapes shown in fig. 7C respectively at the four projected light fields (T1, T2, T3, T4) formed by diffraction by the diffractive optical element, then after the light signals emitted by the respective light source partitions (i.e., the incident light fields of the diffractive optical element) are incident on the diffractive optical element 12, the actually required light fields of the respective partitions may be included in the designed light field of the diffractive optical element in angular space coordinates, where the actually required light field areas are the dashed boxes shown in fig. 7C. Therefore, through the special pattern design of the projected light field of the diffractive optical element, the distortion in all directions existing in the projection process can be compensated, so that the required subarea lighting effect is realized.

Of course, in another example of the present invention, a collimating unit 13 may be disposed between the light source unit 11 and the non-partitioned diffractive optical element 12, so as to collimate the optical signal emitted by the light source unit 11, and then make the collimated optical signal incident on the diffractive optical element 12, so as to form an incident light field having an elliptical shape on the surface of the diffractive optical element 12.

Further, when the diffractive optical element is not provided in the zone TOF apparatus but only the collimating unit is provided, the light fields projected by the VCSEL light source and the collimating lens in cooperation may be projected light fields T1, T2, T3, T4 formed within a small angle of view, and correspond to VCSEL light source zones V1, V2, V3, V4 in this order. As shown in fig. 8A, after the diffractive optical element 12 is added to the optical path, the diffractive optical element 12 may copy and splice the original field angle by 3 × 3 to form a larger field angle, that is, the light field projected by the VCSEL light source, the collimator lens, and the diffractive optical element in cooperation may be 3 × 3 projected light fields T1, T2, T3, and T4 (as shown in fig. 8B) formed in the larger field angle, so that the zonal illumination corresponding to the VCSEL light source can be realized in the same manner.

It should be noted that, according to the first or second embodiment of the present invention, in the section TOF apparatus 1 of the present invention, one light source section may be individually illuminated at intervals of the first predetermined time in sequence, so that different light source sections illuminate corresponding field-of-view sections at different times, and then depth information of corresponding one field-of-view section is detected at different times. Therefore, after one period is finished, the whole target view field can be illuminated, and the whole target view field can be detected.

Preferably, the first predetermined time is not less than the ratio between twice the maximum detection distance and the speed of light, so as to avoid mutual interference between the optical signals emitted by different segments of the light source, which helps to improve the detection accuracy of the segmented TOF apparatus.

More preferably, all the light source sections in the section TOF apparatus may be sequentially illuminated in rows or columns, or may be randomly sequentially illuminated, as long as all the light source sections are illuminated within one detection period.

It is worth noting that the power consumption of the same section TOF apparatus is proportional to the maximum detection distance, that is, the farther the maximum detection distance of the section TOF apparatus is, the larger the power consumption required by the section TOF apparatus is; while when the detection distance of the zone TOF apparatus is smaller than the target field of view of maximum detection distance, a part of the power consumption of the zone TOF apparatus will be wasted for maintaining the maximum detection distance, since the detection of the target field of view can be completed even if the maximum detection distance of the zone TOF apparatus becomes smaller. It will be appreciated that the maximum detection distance of the segmented TOF apparatus is the maximum distance detected by one of the light source segments of the segmented TOF apparatus operating at operating power.

Therefore, in the above example of the present invention, the section TOF apparatus may further adjust the operating power of the light source unit of the section TOF apparatus according to the maximum depth of the target field of view, so that the maximum detection distance of the section TOF apparatus is substantially equal to the maximum depth of the target field of view.

It is worth mentioning that in some embodiments of the present invention, the light source unit in the projection device 10 of the segmented TOF device 1 may not be segmented, but the overall size of the light source unit is reduced, so as to detect different segments of the field of view according to a certain time sequence by changing the propagation angle of the optical signal emitted by the light source unit, and still enable detection of the entire target field of view with lower power consumption.

According to another aspect of the present invention, an embodiment of the present invention further provides a projection device 10, wherein the projection device 10 may include a light source unit 11 and a diffractive optical element 12. The light source unit 11 includes at least two light source partitions 111, and the at least two light source partitions 111 are lit up at a timing to divisionally emit light signals. The diffractive optical element 12 is correspondingly disposed in the light emitting paths of the at least two light source partitions 111 of the light source unit 11, and is configured to perform a diffraction process on the light signal emitted through each light source partition 111 to form a partitioned projected light field and project the partitioned projected light field to a target field of view, so that the receiving device receives the light signal reflected from the target field of view in a time-sharing manner to determine the depth information of the target field of view by measuring the flight time of the light signal.

Illustrative method

According to another aspect of the present invention, an embodiment of the present invention further provides a method of manufacturing the segmented TOF apparatus. Specifically, as shown in fig. 9, the method of manufacturing the partitioned TOF apparatus may include the steps of:

s100: arranging a light source unit, wherein the light source unit comprises at least two light source partitions, and the at least two light source partitions are used for being lightened according to a certain time sequence so as to emit light signals in a partition mode;

s200: correspondingly arranging a diffractive optical element on the light emitting paths of the at least two light source subareas of the light source unit, wherein the diffractive optical element is used for performing diffraction processing on the light signals emitted by each light source subarea to form a subarea projected light field and project the subarea projected light field to a target field of view; and

s300: and a receiving device is arranged, wherein the receiving device is used for receiving the optical signals reflected from the target field of view in a time-sharing manner so as to determine the depth information of the target field of view by measuring the flight time of the optical signals.

It is noted that, in an example of the present invention, as shown in fig. 9, the method for manufacturing a segmented TOF apparatus may further include the steps of:

s400: and arranging a collimation unit between the light source unit and the diffractive optical element, wherein the collimation unit is used for collimating the optical signal emitted by the light source partition of the light source unit to form a collimated optical signal, so that the diffractive optical element diffracts the collimated optical signal.

Illustrative electronic device

According to another aspect of the present invention, an embodiment of the present invention further provides an electronic device. Illustratively, as shown in fig. 10, the electronic device includes an electronic device body 800 and at least one above-mentioned section TOF apparatus 1, wherein the section TOF apparatus 1 is configured on the electronic device body 800 and is used for detecting a target field of view through the section TOF apparatus 1. In particular, the segmented TOF apparatus 1 includes a projection apparatus and a reception apparatus, wherein the projection apparatus includes a light source unit and a diffractive optical element, wherein the light source unit includes at least two light source segments, and the at least two light source segments are configured to be illuminated at a timing sequence to emit light signals in segments; wherein the diffractive optical element is correspondingly arranged on the light-emitting paths of the at least two light source subareas of the light source unit and is used for performing diffraction processing on the light signals emitted by each light source subarea to form a subarea projection light field and project the subarea projection light field to the target visual field; wherein the receiving means is arranged to receive the reflected light signals from the target field of view time-divisionally to determine depth information of the target field of view by measuring the time of flight of the light signals.

It is noted that the electronic device body 800 may be any device or system capable of configuring the segmented TOF apparatus 1, such as glasses, a head-mounted display device, an augmented reality device, a virtual reality device, a smart phone, or a mixed reality device. It will be understood by those skilled in the art that although the electronic device body 800 is implemented as AR glasses in fig. 10, it does not limit the content and scope of the present invention.

It should also be noted that in the apparatus, devices and methods of the present invention, the components or steps may be broken down and/or re-combined. These decompositions and/or recombinations are to be regarded as equivalents of the present invention.

The previous description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.

Claims

1. A zoned TOF apparatus, comprising:

a projection device, wherein the projection device comprises:

2. The zoned TOF apparatus of claim 1, wherein said at least two light source zones are adapted to have a one-to-one correspondence with at least two field zones of the target field of view, and each of the field zones has an area smaller than the area of the target field of view.

3. The zoned TOF apparatus of claim 2, wherein the surface micro-nano-structure of the diffractive optical element is designed according to the field of view zone of the target field of view such that the projected light field formed by diffraction of the diffractive optical element matches the field of view zone.

4. The zoned TOF apparatus of claim 3, wherein the light source unit is a VCSEL light source.

5. The zoned TOF apparatus of claim 4, wherein the diffractive optical element is provided with at least two diffractive zones, and the diffractive zones of the diffractive optical element are in one-to-one correspondence with the light source zones of the light source unit for diffractive processing of the light signals emitted via the corresponding light source zones.

6. The zoned TOF apparatus of claim 5, wherein a spacing between adjacent ones of the light source zones is greater than a product of a mounting distance of the diffractive optical element and a tangent of a divergence half-angle of a light signal emitted via the light source zone.

7. The zoned TOF apparatus of claim 4, wherein said diffractive optical element is provided with only one diffractive zone and said diffractive zones correspond to all of said light source zones for time-divisionally diffracting light signals emitted via different said light source zones.

8. The zoned TOF apparatus of any of claims 1 to 7, wherein each of said light source zones is rectangular, circular or elliptical in shape.

9. The zoned TOF apparatus of claim 8, wherein a shape of an area where the light signal emitted via the light source zone is incident on the surface of the diffractive optical element is kept consistent with a shape of the light source zone.

10. The zone TOF apparatus of any one of claims 1 to 7, wherein the projection apparatus further comprises a collimation unit, wherein the collimation unit is arranged between the light source unit and the diffractive optical element and is configured to collimate the light signal emitted via the light source zones of the light source unit to form a collimated light signal such that the diffractive optical element diffracts the collimated light signal.

11. The zoned TOF apparatus of claim 10, wherein the collimating unit is a collimating lens.

12. The zoned TOF apparatus of claim 10, wherein an area of the surface of the diffractive optical element on which the optical signal collimated by the collimating unit is incident is shaped as an ellipse.

13. The segmented TOF apparatus of claims 1 to 7, wherein said diffractive optical element is further adapted to replica splice optical signals emitted via said light source segments to form a larger field angle.

14. A method of manufacturing a zoned TOF apparatus, comprising the steps of:

15. The method of manufacturing a zoned TOF apparatus as in claim 14, further comprising the steps of:

16. Projection apparatus, characterized in that it comprises:

17. The projection device of claim 16, wherein the at least two light source zones are adapted to have a one-to-one correspondence with at least two field zones of the target field of view, and each of the field zones has an area smaller than the area of the target field of view.

18. The projection device according to claim 16 or 17, further comprising a collimating unit, wherein the collimating unit is disposed between the light source unit and the diffractive optical element, and the collimating unit is configured to collimate the optical signal emitted via the light source partition of the light source unit to form a collimated optical signal, such that the diffractive optical element diffracts the collimated optical signal.

19. An electronic device, comprising:

an electronic device body; and

a projection device, wherein the projection device comprises: