Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
MULTIPLE FUNCTION THREE DIMENSIONAL SCANNER
Document Type and Number:
WIPO Patent Application WO/2020/182301
Kind Code:
A1
Abstract:
An opto-electromechanical apparatus includes a substrate having a first end and a second end. A micro-electro mechanical systems (MEMS) mirror is disposed on the first end of the substrate. A multi-diode laser array is disposed on the second end of the substrate. A photo detector disposed between the MEMS mirror and the laser array. The MEMS mirror is configured to reflect light projected from the multi-diode laser array away from the apparatus and reflect return light onto the photo detector. This provides a single opto-electromechanical package that supports multiple functions using beam scanning projection methods.

Inventors:
EROMAKI MARKO (SE)
SALMELIN EERO (SE)
TERHO MIKKO (SE)
Application Number:
PCT/EP2019/056206
Publication Date:
September 17, 2020
Filing Date:
March 13, 2019
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
HUAWEI TECH CO LTD (CN)
EROMAKI MARKO (FI)
International Classes:
H04N9/31
Domestic Patent References:
WO2009031094A12009-03-12
Foreign References:
US20170285343A12017-10-05
Other References:
UNKNOWN: "Optical microphones", 12 March 2019 (2019-03-12), XP055640775, Retrieved from the Internet [retrieved on 20191108]
Attorney, Agent or Firm:
KREUZ, Georg (DE)
Download PDF:
Claims:
CLAIMS

1. An opto-electromechanical apparatus (100) comprising: a substrate (102) having a first end and a second end; a micro-electro mechanical systems (MEMS) mirror (120) disposed on the first end of the substrate (102); a multi-diode laser array (128) disposed on the second end of the substrate (102); and a photo detector (126) disposed between the MEMS mirror (120) and the laser array (128), wherein the MEMS mirror (120) is configured to reflect light projected from the multi diode laser array (128) away from the apparatus and reflect return light onto the photo detector (126).

2. The opto-mechanical apparatus (100) according to claim 1, further comprising a lightguide cover (110) disposed on top of the substrate (102) and over the MEMS mirror (120) and the multi-diode laser array (128).

3. The opto-mechanical apparatus (100) according to any one of claims 1 or 2 further comprising an optical prism (112) disposed in a top portion of the lightguide cover (110) and configured to pass light to and from the MEMS mirror (120)

4. The opto-mechanical apparatus (100) according to any one of the preceding claims further comprising an optical microphone (114) disposed in a top of the lightguide (110), the optical microphone (114) being aligned with optical prism (112) and the photo detector (126).

5. The opto-mechanical apparatus (100) according to claim 4, wherein the optical microphone (112) comprises a thin membrane unit.

6. The opto-electromechanical apparatus (100) according to any one of claims 4 or 5, further comprising a frame housing (117) of the optical prism (112), the frame housing (117) configured to support the optical microphone (114).

7. The opto-mechanical apparatus (100) according to any one of the preceding claims wherein the MEMS mirror (120) comprises a two axis MEMS based tilting mirror.

8. The opto-electromechanical apparatus (100) according to any one of the preceding claims herein the MEMS mirror (120) is configured to reflect laser light projected from the multi-diode laser (128) onto a scenery surface for image generation.

9. The opto-electromechanical apparatus (100) according to any one of the preceding claims wherein the MEMS mirror (120) is configured to reflect a received infra-red beam onto the photo detector (126).

10. The opto-electromechanical apparatus (100) according to any one of the preceding claims wherein the multi-diode laser array (128) comprises one or more of a red laser, a green laser, a blue laser, an ultraviolet laser and an infrared laser.

11. The opto-electromechanical apparatus (100) according to any one of the preceding claims wherein a laser beam from the multi-diode laser (128) is configured to reflect from the optical microphone (114) to the photo detector (126) and is configured to be transformed into an audio signal.

12. The opto-electromechanical apparatus (100) according to any one of the preceding claims, wherein the apparatus (100) is configured to be disposed on smart eyeglass wear for tracking eye movements.

13. The opto-electromechanical apparatus (100) according to any one of the preceding claims, wherein the apparatus (100) is configured to be disposed in a mobile communication device.

Description:
MULTIPLE FUNCTION THREE DIMENSIONAL SCANNER

TECHNICAL FIELD

[0001] The aspects of the present disclosure relate generally to scanning devices and more particularly to a single optical device for multiple scanning functions.

BACKGROUND

[0002] There are a number of different consumer based optical scanning applications and devices. Examples include, but are not limited to pico projectors that provide a consumer based application using light beam projection on scenery; Time of Flight (ToF) devices that measure the time between outgoing and incoming light for detecting distances; spectrometers that measure the wavelengths of reflected light from an object and eye tracking cameras that detect the movements of eye in augmented reality (AR) and virtual reality (VR) applications. Each system is a single, separated, standalone unit which performs single function.

[0003] However, discrete, non-integrated, systems are needed for these types of applications. Integration of these types of image projection and image scanning systems to mobile devices is a challenge due to size and cost problems.

[0004] Accordingly, it would be desirable to be able to provide a system that addresses at least some of the problems identified above.

SUMMARY

[0005] It is an object of the disclosed embodiments to provide an apparatus and method that enables the use of a single optical engine for multiple functions in a mobile communication device. This object is solved by the subject matter of the independent claims. Further advantageous modifications can be found in the dependent claims.

[0006] According to a first aspect the above and further objects and advantages are obtained by an opto -electromechanical apparatus. In one embodiment, the opto- electromechanical apparatus includes a substrate having a first end and a second end. A micro electro mechanical systems (MEMS) mirror is disposed on the first end of the substrate. A multi diode laser array is disposed on the second end of the substrate. A photo detector disposed between the MEMS mirror and the laser array. The MEMS mirror is configured to reflect light projected from the multi-diode laser array and reflect return light onto the photo detector. Return light, as that term is used herein, generally refers to light that is reflected from an object or scenery. The aspects of the disclosed embodiments provide a single opto-electromechanical package that supports multiple functions using beam scanning projection methods.

[0007] In a possible implementation form of the apparatus according to the first aspect a lightguide cover is disposed on top of the substrate and over the MEMS mirror and the multi diode laser array. The aspects of the disclosed embodiments provide a shared opto- electromechanical structure resulting in compact unit size, cost-effective technical design and high consumer benefit.

[0008] In a possible implementation form of the apparatus and optical prism is disposed in an opening and a top portion of the light guide cover. The optical prism is configured to pass light to and from the MEMS mirror. The aspects of the disclosed embodiments provide a shared opto-electromechanical structure. [0009] In a possible implementation form of the apparatus an optical microphone is disposed in an opening in a top of the lightguide. The optical microphone is aligned with the optical prism and the photo detector. The aspects of the disclosed embodiments provide a scanning based optical engine that can be used as a microphone.

[0010] In a possible implementation form of the apparatus the optical microphone comprises a thin membrane unit. The aspects of the disclosed embodiments provide a scanning based optical engine can be used as a microphone. The thin membrane is vibrating due to external sound pressure and is detected via optical measurement.

[0011] In a possible implementation form of the apparatus a frame housing of the optical prism is configured to support the optical microphone. The aspects of the disclosed embodiments provide a scanning based optical engine can be used as a microphone. Reflected light can be transformed into an audio signal representing clear, true-to- source sound

[0012] In a possible implementation form of the apparatus the MEMS mirror comprises a two axis MEMS based tilting mirror. The aspects of the disclosed embodiments provide a compact opto-electromechanical unit which has multiple functions, each of which utilizes the two axis MEMS mirror for projecting onto scenery or detecting something from the scenery. This integrated unit has cost, size, manufacturability and technology advantages that enables new experiences with high consumer appeal.

[0013] In a possible implementation form of the apparatus the MEMS mirror is configured to reflect laser light from the multi-diode laser onto a scenery surface for image generation. The aspects of the disclosed embodiments provide a single opto-electromechanical package to support multiple functions using beam scanning projection methods. [0014] In a possible implementation form of the apparatus the MEMS mirror is configured to reflect return light, such as a returned infra-red beam, onto the photo detector. The aspects of the disclosed embodiments provide for using in infrared laser to determine time-of- flight in the shared opto- electromechanical structure.

[0015] In a possible implementation form of the apparatus the multi-diode laser array comprises one or more of a red laser, a green laser, a blue laser, an ultraviolet laser and an infrared laser. The shared opto-electromechanical structure of the disclosed embodiments can provide a spectrometer function,

[0016] In a possible implementation form of the apparatus a laser beam from the multi diode laser is configured to reflect from the optical microphone to the photo detector and be transformed into an audio signal. Reflected light in the shared opto-electromechanical structure can be transformed into an audio signal.

[0017] In a possible implementation form of the apparatus, the apparatus is configured to be disposed on smart eyeglass wear for tracking eye movements. The shared opto- electromechanical structure of the disclosed embodiments has a compact size enabling use with devices such as smart eyeglasses.

[0018] In a possible implementation form of the apparatus, the apparatus is configured to be disposed in a mobile communication device. The shared opto-electromechanical structure of the disclosed embodiments has a compact size enabling use with devices such as smart mobile phones. [0019] These and other aspects, implementation forms, and advantages of the exemplary embodiments will become apparent from the embodiments described herein considered in conjunction with the accompanying drawings. It is to be understood, however, that the description and drawings are designed solely for purposes of illustration and not as a definition of the limits of the disclosed invention, for which reference should be made to the appended claims. Additional aspects and advantages of the invention will be set forth in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. Moreover, the aspects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In the following detailed portion of the present disclosure, the invention will be explained in more detail with reference to the example embodiments shown in the drawings, in which:

[0021] Figures 1 illustrates a perspective view of exemplary apparatus incorporating aspects of the disclosed embodiments.

[0022] Figure 2 illustrates an assembly view of an exemplary apparatus incorporating aspects of the disclosed embodiments.

[0023] Figure 3 illustrates a sectional view of an exemplary apparatus incorporating aspects of the disclosed embodiments.

[0024] Figure 4 illustrates a sectional view of an exemplary apparatus incorporating aspects of the disclosed embodiments showing the projection of laser light.

[0025] Figure 5 illustrates a sectional view of an exemplary apparatus incorporating aspects of the disclosed embodiments showing the projection and reflection of an infrared beam.

[0026] Figure 6 illustrates automatic Keystone correction by software with an apparatus incorporating aspects of the disclosed embodiments.

[0027] Figure 7 illustrates a sectional view of an exemplary apparatus incorporating aspects of the disclosed embodiments being used for retina projection.

[0028] Figure 8 illustrates a smart glass implementation of an exemplary apparatus incorporating aspects of the disclosed embodiments. [0029] Figure 9 illustrates a sectional view of an exemplary apparatus incorporating aspects of the disclosed embodiments being used as a spectrometer.

[0030] Figure 10 illustrates a sectional view of an exemplary apparatus incorporating aspects of the disclosed embodiments being used as an optical microphone.

DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENTS

[0031] Referring to Figure 1 there can be seen a perspective view of an exemplary apparatus 100 incorporating aspects of the disclosed embodiments. The aspects of the disclosed embodiments are directed to an apparatus or device 100 that that provides multiple functions using beam scanning projection methods in a single opto-electromechanics package with a single optical engine. The compact unit utilizes a set of lasers in a laser array 128, a photo detector 126, and a micro-electro mechanical systems (MEMS) mirror 120 for producing several functions. Both, reflected light, or a return beam and (unit) internal reflections can be separated with an optical reflector 130 and analyzed with the photo detector 126 array for different wavelengths. The MEMS mirror 120 is able to cover the scenery with wide degree of optical tilt projection angle

[0032] As is shown in Figure 2 the components of the apparatus 100 are disposed on a substrate 102 that has a first end and a second end. The micro-electro mechanical systems (MEMS) mirror 120 is disposed on the first end of the substrate 102. In one embodiment the mirror 120 is a two-axis tilting MEMS mirror that is disposed in a housing 122. The multi-diode laser array 128 is disposed on the second end of the substrate. In one embodiment the laser array 128 can include a set of small edge-emitting lasers such as visible red, green, blue, UV, and IR, coupled together with an optical fiber combiner. The photo detector 126 is disposed between the MEMS mirror 120 and the laser array 128. The photo detector 126, also referred to herein as a photo sensor or photo sensor array, can be a small complementary metal-oxide-semiconductor (CMOS) image sensor, equipped with suitable filters and micro lenses

[0033] In one embodiment, hardware elements 106, such as one or more processors and drivers for example, can also be disposed on the substrate 102. An example of Figure 2, the hardware elements are disposed on an end of the substrate 102. In alternate embodiments the hardware elements 106 can be disposed of any suitable location on the substrate 102. An interconnection member 104 can also be used to connect the apparatus 104 other suitable electrical and electronic components. This can include for example other processors and driver circuitry as well as electrical power. In the example of Figure 2 the interconnection member 104 is a cable with a connector.

[0034] Referring also to Figure 3, in one embodiment, the apparatus 100 can include a plastic light guide 110. The plastic light guide 110 can be used to cover and protect the components that are disposed on the substrate 102. In the example of Figure 2 the plastic light guide 110 can include an opening 116. The opening 116 is configured to receive an optical prism 112. An optical microphone 114, in the form of a thin membrane member, is disposed in a membrane suspension frame, or frame housing 117, of the optical prism 112.

[0035] As is shown in Figure 3, the apparatus 100 includes an optical reflector member or element 130. The optical reflector element 130 can be part of the light guide 110 or a separate member. As shown in Figure 3, the optical reflector element 130 includes a first reflecting portion 132, a second reflecting portion 134 and a third reflecting portion 136. The reflecting portions 132-136 are configured and suitably angled to reflect light projected from the laser array 128 onto a surface of the MEMS mirror 120. For example, the laser light generated by the laser array 128 is configured to be reflected by the first reflecting portion 132 towards the second reflecting portion 134 and then to the third reflecting portion 136. From the third reflecting portion 136 light is reflected onto the surface of the MEMS mirror 120. An example of this is also shown in Figure 4.

[0036] The apparatus 100 is configured to provide multiple functions. Some of these functions include, but are not limited to, image projection and augmented reality (AR) retina (eye) projection, a spectrometer function, a time-of-flight function and an optical microphone function. The different working modes of the apparatus 100 for these functions are described below.

[0037] Figure 4 illustrates image projection and AR retina projection. In this example the laser light 402 generated by the laser array 128 includes red, green and blue. The red, green and blue lasers are projected from the laser array 128 along the optical path 404 and via the MEMS mirror 120 onto the surface of a scenery for image generation.

[0038] In this example, MEMS mirror 120 is performing high frequency scanning motion along two axis, pitch and yaw (e.g. raster scanning or Fissajous-pattern based). In one embodiment the infrared (IR) laser of the laser array 128 can be activated for time-of-flight use which allows the determination of the projection distance as well as plane shape scanning.

[0039] Figure 5 illustrates one example of time-of-flight operation. The projected infrared beam 502 is reflected back as returning or reflected infrared beam 504 along a reverse path through the optical prism 112 to the MEMS mirror 120. The returning or reflected infrared beam 504 may also be referred to as return light. In this example a fourth reflecting portion 138 of the reflecting number 130 directs the returning infrared beam 504 from the MEMS mirror 120 onto the photo detector 126. The time-of-flight function is configured to operate during image projection. When time-of-flight function is used to support normal camera features such as fast autofocus (AF), then the apparatus 100 can be configured to operate in time-of-flight only mode.

[0040] Referring to Figure 6, time-of-flight measurement provides the ability to project the image 602 at a proper alignment towards the viewer on tilted/uneven surface. Example 6A illustrates a normal projection of the image 602. In example 6B, the projection of the image 602 is distorted. Example 6C illustrates the corrected projection of the image 602 from example 602. In one embodiment, Keystone correction can be applied to correct the distorted projection. The correction can be carried out automatically by software. Thus, in combination with laser projection, which is focus free, the image 602 always stays sharp and non-distorted.

[0041] Figures 7 and 8 illustrate use of the apparatus 100 for augmented reality retina projection. In this example the set of lasers 702 includes red, green and blue (RGB) lasers. The set of lasers 702 is projecting an image through the pupil and lens at the back of the eye 710 and onto the retina 712. A half mirror lens 706, or beam splitter, is typically used as a member and augmented reality systems. In one embodiment, the half mirror lens 706 comprises the lens of the augmented reality glasses 800 shown in Figure 8.

[0042] During movement of the MEMS mirror 120, using for example, raster/lissajous patterns, the image is formed on the human retina 712 using the projected 702 RGB lasers. Simultaneously the IR emitter projects a pattern on the eye 710 and receives return reflection. The return beam 704 is reflected onto the MEMS mirror 120. Depending on eye movements, the location of the eye box 714 can be changed by varying the reflection point on the half mirror 706 with the scanning angle of the MEMS mirror 120.

[0043] In the example of Figure 9, an additional ultraviolet laser (UV) is included along with the red, green, blue, lasers in the set of projecting lasers 902. The use of the ultraviolet laser in the set of projecting lasers 902 enables the apparatus 100 to provide a spectrometer function. In this example, the set of projecting lasers 902 are projected onto the object 904 on the scenery. Based on the absorbed and reflected wavelengths, the returning beams 906, indicated in dashed lines, are reflected via the MEMS mirror 120 onto the photo sensor array 126 to be measured. The photo sensor array 126 is configured to analyze the wavelengths of the reflected beams 906. In one embodiment, the MEMS mirror 120 is configured to perform coarse or fine scanning of selected areas.

[0044] Figure 10 illustrates the use of the apparatus 100 for optical microphone sensing.

In this example the membrane suspension frame 117 includes a thin membrane member, or optical microphone 114. The thin membrane member 114 can comprise a polymer or semiconductor (MEMS) fabricated metal or silicon membrane. By activating a suitable laser diode, the beam 140 reaches the membrane 114. The reflected beam 142 is reflected back onto the photo sensor array 126. Sound waves 150 hitting the membrane 114 cause the membrane 114 to vibrate. This vibration will change the characteristics of the light reflection. The reflected light 142 is transmitted through an optical path back onto the photo sensor array 126. The reflected light 142 is transformed into an audio signal representing clear, true to source sound. [0045] The aspects of the disclosed embodiments are directed to a compact opto- electromechanical device which has multiple functions. The device performs beam steering operations by scanning for outgoing light and analyzing technical properties of incoming light. The incoming light data is also used for beam steering operations. The multiple functions utilize a tilting two access MEMS mirror for projecting something on the scenery or detecting something from the scenery. The single opto -electromechanical device is able to generate add on projections on the scenery. The device is also able to receive feedback information from the scenery in terms of distances and shapes of objects for creating three-dimensional digital representations and time-of-flight functionality by scanning. The three-dimensional scenery representation can be utilized to enhance the operation of normal cameras on a mobile communication device, provide faster auto focus, focus and object tracking. The three- dimensional scenery representation can also be utilized in optical correction of the image projection on uneven and tilted services using for example Keystone adjustment.

[0046] The device is able to analyze material property of the objects on the scenery in a spectroscopy operation. The device is also able to detect changes in sound pressure providing a microphone functionality. When attached to smart glasses the unit is able to track the movement of the eye for adjusting the image projection location and provide electrical eye box adjustment. The unit is able to generate an image on the human eye retina and provide a different type of mixed reality functionality.

[0047] Thus, while there have been shown, described and pointed out, fundamental novel features of the invention as applied to the exemplary embodiments thereof, it will be understood that various omissions, substitutions and changes in the form and details of devices and methods illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit and scope of the presently disclosed invention. Further, it is expressly intended that all combinations of those elements, which perform substantially the same function in substantially the same way to achieve the same results, are within the scope of the invention. Moreover, it should be recognized that structures and/or elements shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.