Optical ranging module and electronic device

Abstract

An optical ranging module and an electronic device, the optical ranging module defining an object side and an element side opposite to the object side, the optical ranging module comprising: an optical emission unit including a first optical lens group and a light source in order from the object side to the element side; the optical receiving unit sequentially comprises a second optical lens group and an optical sensor from the object side to the element side; the supporting cover comprises two openings capable of penetrating through the object side and the element side, and the first optical lens group of the optical transmitting unit and the second optical lens group of the optical receiving unit are arranged in the two openings respectively; and the optical filter layer is made of a material through which only infrared rays can penetrate, and is arranged on a light wave transmitting path of the optical transmitting unit and / or a light wave receiving path of the optical receiving unit.

Description

TECHNICAL FIELD

[0001] The present application relates to an optical distance measurement module, and particularly relates to an electronic device comprising the optical distance measurement module. BACKGROUND

[0002] Time of flight (ToF) is a method of measuring distance by sending light waves to a target object, receiving the light waves returned from the target object, and detecting the flight (round trip) time of the light waves. Currently, three-dimensional cameras of electronic devices mainly use optical distance measurement modules with Tof, which include optical transmitting units and optical receiving units.

[0003] However, the optical transmitting unit usually uses a vertical cavity surface emitting laser (VCSEL) as a light source. The light waves between the round trip target object include not only infrared light, but also visible light and other waveband light. In this case, if the signal-to-noise ratio is too low, the distance measurement may be inaccurate.

[0004] On the other hand, due to the high reflectivity of the optical lens itself, the appearance of the optical unit assembly will form a white reflection, resulting in low color consistency.

[0005] Therefore, there is a need to provide an optical distance measurement module and an electronic device that can solve the above problems. SUMMARY

[0006] An object of the present application is to provide an optical distance measurement module, wherein the optical filter layer is arranged on the object side of the light emitting unit and the optical receiving unit; further, the optical filter layer is used to filter out visible light sources, and the optical filter layer and the support cover have similar colors, which can improve the distance measurement accuracy and appearance color consistency of the optical distance measurement module.

[0007] According to the above-mentioned purpose, the present application provides an optical distance measuring module, which has an object side and a component side opposite to the object side, and comprises: an optical emitting unit, which comprises a first optical lens group and a light source in sequence from the object side to the component side; an optical receiving unit, which comprises a second optical lens group and an optical sensor in sequence from the object side to the component side; a support cover, which comprises two openings through which the object side and the component side can be penetrated, and the first optical lens group of the optical emitting unit and the second optical lens group of the optical receiving unit are arranged in the two openings respectively; and an optical filter layer, which is made of a material through which only infrared rays can penetrate, and is arranged on a light wave emitting path of the optical emitting unit and / or a light wave receiving path of the optical receiving unit.

[0008] Optionally, the optical filter layer is arranged on an object side surface of a lens closest to the object side in the first optical lens group and / or an object side surface of a lens closest to the object side in the second optical lens group.

[0009] Optionally, the optical filter layer is arranged on an object side surface of a lens closest to the object side in the first optical lens group and / or an object side surface of a lens closest to the object side in the second optical lens group.

[0010] Optionally, the optical filter layer is arranged on an object side surface of a lens closest to the object side in the first optical lens group and / or an object side surface of a lens closest to the object side in the second optical lens group.

[0011] Optionally, the optical filter layer is arranged on an object side surface of a lens closest to the object side in the first optical lens group and / or an object side surface of a lens closest to the object side in the second optical lens group.

[0012] Optionally, when the two protective glasses are located on a side of the first optical lens group facing the object side and a side of the second optical lens group facing the object side, the two protective glasses are integrally formed.

[0013] Optionally, when the two protective glasses are located on a side of the first optical lens group facing the object side and a side of the second optical lens group facing the object side, the two protective glasses are integrally formed.

[0014] Optionally, the optical filter layer is arranged on an object side surface of a lens closest to the object side in the first optical lens group and / or an object side surface of a lens closest to the object side in the second optical lens group.

[0015] Optionally, a transparent cover is further included on one side of the second optical lens group of the optical receiving unit facing the object side or the element side, wherein the optical filter layer is disposed on one of the object side surface or the element side surface of the transparent cover, and the optical filter layer is also disposed on an object side surface of the first optical lens group of the optical emitting unit.

[0016] Optionally, the optical filter layer and the support cover have an optical reflectivity less than 5%.

[0017] Optionally, the optical filter layer is a black ink and has a thickness not more than 50 μm.

[0018] The present application further provides an electronic device, comprising: a housing; the optical distance measuring module as described, disposed in the housing; a driving element, disposed in the housing and electrically connected to the optical emitting unit; and a processing element, disposed in the housing and electrically connected to the optical sensor.

[0019] According to the optical distance measuring module of the present application, the optical filter layer can allow infrared light to pass, and the optical filter layer and the support cover have similar optical reflectivity, thus reducing glare and improving the comfort of human eye vision. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 FIG. 1 is a cross-sectional view of an optical distance measuring module according to a first embodiment of the present application, showing that the optical filter layer is disposed on the object side of the optical emitting unit, or on the object side of the optical receiving unit, or on the object side of both the optical emitting unit and the optical receiving unit.

[0021] Figure 1A FIG. 2 is a side view of the optical distance measuring module according to an embodiment of the present application.

[0022] Figure 2 FIG. 3 is a cross-sectional view of an optical distance measuring module according to a second embodiment of the present application, showing that a transparent cover is disposed between the optical filter layer and the optical emitting unit.

[0023] Figure 3 FIG. 4 is a cross-sectional view of an optical distance measuring module according to a third embodiment of the present application, showing that a transparent cover is disposed between the optical filter layer and the optical emitting unit, and a transparent cover is disposed between the optical filter layer and the optical receiving unit.

[0024] Figure 4 FIG. 5 is a diagram of the optical properties of the filter layer according to the present application.

[0025] Figure 5 FIG. 6 is a cross-sectional view of an electronic device according to an embodiment of the present application.

[0026] In the figure: O: object side O1: object side surface of the first optical lens group O2: object side surface of the second optical lens group O3: object side surface of the transparent cover O4: element side surface of the transparent cover E: element side a1: first central axis a2: second central axis 1, 2, 3: optical distance measuring module 110, 210, 310: optical emitting unit 111, 211, 311: first lens barrel 112, 212, 312: first optical lens group 113, 213, 313: light source 120, 220, 320: optical receiving unit 121, 221, 321: second lens barrel 122, 222, 322: second optical lens group 123, 223, 323: optical sensor 130, 230, 330: support cover 14, 24, 34: base b1: first opening b2: second opening 140, 240, 340: optical filter layer T: target object L10, L20: light wave L11: light wave emitting path L21: light wave receiving path 250, 350: transparent cover 4: electronic device 410: driving element 420: control element C: housing S: plane DETAILED DESCRIPTION

[0027] In order to make the above objectives, features and characteristics of the present application more apparent, comprehensible and easier to understand, the present application will be described in detail below with reference to the drawings.

[0028] Figure 1 A cross-sectional view of an optical distance measuring module of an embodiment of the present application, which shows that the optical filter layer is disposed on the object side of the optical emitting unit and the optical receiving unit. Figure 1A A side view of an optical distance measuring module of a first embodiment of the present application. Please refer to Figure 1 ,Figure 1A The optical distance measuring module 1 defines an object side O and an element side E opposite to the object side, and comprises an optical emitting unit 110, an optical receiving unit 120, a support cover 130, and an optical filter layer 140.

[0029] The optical emitting unit 110 has a first central axis a1 and a first lens barrel 111 surrounding the first central axis a1. A first optical lens group 112 and a light source 113 are sequentially arranged from the object side O to the element side E of the first lens barrel 111. The first optical lens group 112 comprises at least one optical lens. The light source 113 is an infrared light source, which provides an infrared light wave toward the object side O. The light source 113 can be a vertical cavity surface emitting laser (VCSEL) or an edge emitting laser (EEL), but is not limited thereto.

[0030] The optical receiving unit 120 has a second central axis a2 and a second lens barrel 121 surrounding the second central axis a2. A second optical lens group 122 and an optical sensor 123 are sequentially arranged from the object side O to the element side E of the second lens barrel 121. The second optical lens group 122 comprises at least one optical lens. The optical sensor 123 is usually a photosensitive element, which is used to receive light waves passing through the second optical lens group 122. The optical sensor 123 can be a complementary metal oxide semiconductor (CMOS) or a charge coupled device (CCD), but is not limited thereto.

[0031] The support cover (Cap) 130 can be a housing, a surface S of the housing is a plane, having a first opening b1 and a second opening b2 which can communicate with the object side O and the element side E, the first optical lens group 112 of the optical emission unit 110 is disposed in the first opening b1, and the object side surface of the first optical lens group 112 of the optical emission unit 110 and the object side surface of the first opening b1 are both towards the object side O, the light wave L10 of the light source 113 passes through the first optical lens group 112, then through the first opening b1 to the object side O. The second optical lens group 122 of the optical receiving unit 120 is disposed in the second opening b2, the object side surface of the second optical lens group 122 of the optical receiving unit 120 and the object side surface of the second opening b2 are both towards the object side O, the optical sensor 123 receives the light wave L20 from the object side O and through the second optical lens group 122. The support cover 130 can be made of black plastic material, which has a lower optical reflectivity and is not easy to produce glare, the optical reflectivity of the support cover 130 is preferably generally between 2% and 5%.

[0032] The optical distance measuring module 1 further comprises a base 14, the light source 113 is disposed on the base 14, and the optical sensor 123 is disposed on the base 14. The support cover 130 is disposed on the base 14 and defines first and second accommodation spaces with the base 14 for accommodating the optical emission unit 110 and the optical receiving unit 120 respectively.

[0033] The optical filter layer 140 is made of a material that only allows infrared light to pass through, such as infrared ink (for example, the ink supplier: Shenzhen Meilvha Science and Technology Co., Ltd., ink model: MT-IR-2381J), and is arranged on the light wave transmission path L11 of the optical transmission unit 110 and / or the light wave receiving path L21 of the optical receiving unit 120. In this embodiment, the light wave transmission path L11 refers to the path of the light wave L10 emitted by the light source 113, passing through the first optical lens group 112, then passing through the optical filter layer 140, and reaching the target object T; and the light wave receiving path L21 refers to the path of the light wave L20 reflected by the target object T, passing through the optical filter layer 140, then passing through the second optical lens group 122, and reaching the optical sensor 123. The optical filter layer 140 can be arranged on the object side surface O1 of the first optical lens group 112 of the optical transmission unit 110, or arranged on the object side surface O2 of the second optical lens group 122 of the optical receiving unit 120, or arranged on the object side surface O1 of the optical transmission unit 110 and the object side surface O2 of the optical receiving unit 120. In this embodiment, the optical filter layer 140 is arranged on the object side surface O1 of the optical transmission unit 110 and the object side surface O2 of the optical receiving unit 120. The optical filter layer 140 is used to filter out visible light with a wavelength of 360-830 nm. The optical filter layer 140 and the support cover 130 have similar or the same color that is visible to the human eye, such as black, but not limited to this light. When the optical distance measuring module 1 is assembled, the optical filter layer 140 and the support cover 130 can have consistent visual effects. In addition, the optical filter layer 140 and the support cover 130 have similar light reflectivity, such as 2-5%, but not limited to this, so as to reduce glare and improve visual comfort.

[0034] Please refer to Figure 1In the present embodiment, a target object T is located at the object side O of the optical distance measuring module 1. When the optical filter layer 140 is disposed between the target object T and the optical emitting unit 110 and between the target object T and the optical receiving unit 120, the light source 113 of the optical emitting unit 110 emits a light wave L10 along the light wave emitting path L11 via the first optical lens group 112, and the light wave L10 passes through the optical filter layer 140 to project onto the target object T and generate a reflection, forming a light wave L20. The light wave L20 passes through the optical filter layer 140 along the light wave receiving path L21 via the second optical lens group 122, and the light wave L20 is finally received by the optical sensor 123. In another embodiment, a target object T is located at the object side O of the optical distance measuring module 1. When the optical filter layer 140 is disposed only between the target object T and the optical emitting unit 110, the light source 113 of the optical emitting unit 110 emits a light wave L10 along the light wave emitting path L11 via the first optical lens group 112, and the light wave L10 passes through the optical filter layer 140 to project onto the target object T and generate a reflection, forming a light wave L20. The light wave L20 passes through the second optical lens group 122 along the light wave receiving path L21, and the light wave L20 is finally received by the optical sensor 123. In yet another embodiment, a target object T is located at the object side O of the optical distance measuring module 1. When the optical filter layer 140 is disposed only between the target object T and the optical receiving unit 120, the light source 113 of the optical emitting unit 110 emits a light wave L10 along the light wave emitting path L11 via the first optical lens group 112, and the light wave L10 passes through the optical filter layer 140 to project onto the target object T and generate a reflection, forming a light wave L20. The light wave L20 passes through the optical filter layer 140 along the light wave receiving path L21 via the second optical lens group 122, and the light wave L20 is finally received by the optical sensor 123.

[0035] Figure 2 The second embodiment of the optical distance measuring module is shown in the cross-sectional view. Figure 2The difference between the first embodiment and the second embodiment is that the optical distance measuring module 2 defines an object side O and a component side E opposite to the object side, and comprises an optical emitting unit 210, an optical receiving unit 220, a support cover 230, an optical filter layer 240, and a transparent cover 250 (for example, two protective glasses or cover glasses). The optical filter layer 240 is located on the object side surface O3 or the component side surface O4 of the transparent cover 250. The transparent cover 250 can be located on the side of the first optical lens group 212 of the optical emitting unit 210 toward the object side O or on the side of the second optical lens group 222 of the optical receiving unit 220 toward the component side E. The optical filter layer 240 can also be arranged on the object side surface O1 of the first optical lens group 212 of the optical emitting unit 210 or on the object side surface O2 of the second optical lens group 222 of the optical receiving unit 220. In this embodiment, the optical filter layer 240 is located on the object side surface O3 of the transparent cover 250. The transparent cover 250 is located on the side of the first optical lens group 212 of the optical emitting unit 210 toward the object side O. The object side surface O2 of the second optical lens group 222 of the optical receiving unit 220. When the transparent cover 250 and the optical filter layer 240 are arranged on the light wave emitting path L11 of the optical emitting unit 210 or on the light wave receiving path L21 of the optical receiving unit 220, the transparent cover 250 and the optical filter layer 240 can improve the optical performance of the optical emitting unit 210 or the optical receiving unit 220. When the transparent cover 250 and the optical filter layer 240 act as a window cover, they also have dustproof and antifouling functions.

[0036] Figure 3 The third embodiment of the optical distance measuring module of the present application is shown in a cross-sectional view. Please refer to Figure 3 The difference between the first embodiment and the third embodiment is that the optical distance measuring module 3 defines an object side O and a component side E opposite to the object side, and comprises an optical emitting unit 310, an optical receiving unit 320, a support cover 330, an optical filter layer 340, and a transparent cover 350. The optical filter layer 340 is located on the object side surface O3 or the component side surface O4 of the transparent cover 350. The transparent cover 350 can be located on the side of the first optical lens group 312 of the optical emitting unit 310 toward the object side O or on the side of the second optical lens group 322 of the optical receiving unit 320 toward the component side E. In this embodiment, the optical filter layer 340 is located on the object side surface O3 of the transparent cover 350. The transparent cover 350 is located on the side of the first optical lens group 312 of the optical emitting unit 310 toward the object side O. The transparent cover 350 is also located on the side of the second optical lens group 322 of the optical receiving unit 320 toward the object side O.

[0037] The transparent cover 350 can be integrally formed with two protective glasses on one side of the optical emission unit 310 and the optical receiving unit 320 toward the object side O, or integrally formed with two protective glasses on one side of the optical emission unit 310 and the optical receiving unit 320 toward the element side E. The integrally formed two protective glasses (i.e., the transparent cover 350) can improve the assembly accuracy of the optical distance measuring module 1. Alternatively, the transparent cover 350 can be two separate protective glasses on one side of the optical emission unit 310 and the optical receiving unit 320 toward the object side O. The transparent cover 350 has two individual functions, which can improve the assembly yield of the optical distance measuring module 1 when the optical emission unit 310 or the optical receiving unit 320 is a defective product.

[0038] In detail, the optical filter layer 140, 240, 340 in the above-mentioned optical distance measuring module can be an infrared transparent ink material (IR Ink), such as black ink, formed on the object side surface of the lens closest to the object side in the first optical lens group 112, 212, 312, on the object side surface of the lens closest to the object side in the second optical lens group 122, 222, 322, or on the object side surface of the transparent cover 250, 350, by a coating process. The optical filter layer has a thickness of no more than 50 μm. Since the radii of curvature of the object side surfaces of the optical lens and the transparent cover can be different, and considering the uniformity of ink coating, the ink thickness can be between 5 μm and 10 μm, and the coating process can be pad printing, screen printing, or spraying.

[0039] Figure 4 The optical filter layer of the present application has the following optical properties. The material properties of the optical filter layer allow the human eye to perceive black vision in the visible light range, and the infrared transmittance in the near-infrared wavelength range above 800 nm can be selected between 85% and 90% according to the coating thickness of the ink, the working wavelength range, and the color requirements, but is not limited thereto.

[0040] Figure 5 The electronic device 4, such as a smart phone, includes a housing C, the optical distance measuring module 1, 2, 3 is disposed in the housing C, a driving element 410 is disposed in the housing C and electrically connected to the light source 113, 213, 313, and a control element 420 is disposed in the housing C and electrically connected to the optical sensor 123, 223, 323.

[0041] The optical distance measuring module 1 can be applied in an optical system, and can be applied in various fields, such as face recognition of 3D (three-dimensional) image acquisition, automatic focusing or depth sensing shooting function of consumer electronic products, tracking user actions in virtual reality (VR) and augmented reality (AR), driving assistance system (ADAS) or gesture control in automatic driving and automobile industry, positioning and navigation object recognition in robots and industrial automation, and instant distance measurement in unmanned aerial vehicles.

[0042] In summary, the present application is only described as a preferred embodiment of the technical means used to solve the problem, and is not intended to limit the scope of the patent. Any equivalent changes and modifications made in accordance with the scope of the present application are also covered by the scope of the present application.

Claims

1. An optical ranging module, defining an object side and an element side opposite to the object side, characterized in that, And includes: An optical emitting unit includes, from the object side to the element side, a first optical lens group and a light source in sequence; An optical receiving unit includes, from the object side to the element side, a second optical lens group and an optical sensor in sequence; A support cover includes two openings that can penetrate the object side and the component side, and the first optical lens group of the optical emitting unit and the second optical lens group of the optical receiving unit are respectively disposed in the two openings; as well as An optical filter layer, made of a material that is only permeable to infrared light, is disposed on a light emission path of the optical emitting unit and / or a light receiving path of the optical receiving unit.

2. The optical ranging module as described in claim 1, characterized in that, The optical filter layer is disposed on an object-side surface of the first optical lens group of the optical emitting unit and / or an object-side surface of the second optical lens group of the optical receiving unit. The optical filter layer is used to filter out visible light, and the optical filter layer has a similar color to the support cover.

3. The optical ranging module as described in claim 2, characterized in that, The optical filter layer is disposed on the object-side surface of the lens closest to the object side in the first optical lens group and on the object-side surface of the lens closest to the object side in the second optical lens group.

4. The optical ranging module as described in claim 1, characterized in that, The device further includes a transparent cover located on one side of the first optical lens group of the optical emitting unit facing the object side or the element side, and / or on one side of the second optical lens group of the optical receiving unit facing the object side or the element side, and the optical filter layer is disposed on one of the object-side surface or the element-side surface of the transparent cover.

5. The optical ranging module as described in claim 4, characterized in that, The transparent cover consists of two protective glass panes, and the optical filter layer is disposed on either the object-side surface or the component-side surface of the transparent cover.

6. The optical ranging module as described in claim 5, characterized in that, When the two protective glass pieces are located on the side of the first optical lens group facing the object and the side of the second optical lens group facing the object, the two protective glass pieces are integrally formed.

7. The optical ranging module as described in claim 5, characterized in that, When the two protective glass pieces are located on the side of the first optical lens group facing the element and the side of the second optical lens group facing the element, the two protective glass pieces are integrally formed.

8. The optical ranging module as described in claim 1, characterized in that, The device further includes a transparent cover located on one side of the first optical lens group of the optical emitting unit facing the object side or the element side, wherein the optical filter layer is disposed on the object side surface or the element side surface of the transparent cover, and the optical filter layer is also disposed on an object side surface of the second optical lens group of the optical receiving unit.

9. The optical ranging module as described in claim 1, characterized in that, The device further includes a transparent cover located on one side of the second optical lens group of the optical receiving unit facing the object side or the element side, wherein the optical filter layer is disposed on one of the object-side surface or the element-side surface of the transparent cover, and the optical filter layer is also disposed on one object-side surface of the first optical lens group of the optical emitting unit.

10. The optical ranging module as described in claim 1, characterized in that, The optical filter layer and the support cover have an optical reflectivity of less than 5%.

11. The optical ranging module as described in claim 1, characterized in that, The optical filter layer is a black ink and has a thickness of no more than 50 μm.

12. An electronic device, characterized in that, include: A shell; The optical ranging module as described in any one of claims 1 to 11 is disposed within the housing; A driving element is disposed inside the housing and electrically connected to the light source; as well as A control element is disposed within the housing and electrically connected to the optical sensor.

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