Google Patent | Electronically controlling optical transmission of a lens of a camera in variable lighting

Patent: Electronically controlling optical transmission of a lens of a camera in variable lighting

Drawings: Click to check drawins

Publication Number: 20210136271

Publication Date: 20210506

Applicant: Google

Abstract

Methods, systems, and apparatus, for controlling optical transmission of a lens of a camera. A method includes obtaining a first image from a camera, determining that the first image does not satisfy an image requirement, in response to determining that the first image does not satisfy an image requirement, increasing an optical transmission of a lens of the camera, and, obtaining a second image with the camera while the optical transmission of the lens of the camera is increased.

Claims

  1. (canceled)

  2. A computer-implemented method, comprising: obtaining, by a computing system, an image requirement for an image to be captured; determining, by the computing system, that an optical transmission of a lens of a camera has an initial optical transmission level before capturing the image; determining, by the computing system based on both the image requirement for the image and the initial optical transmission level of the lens, to increase the optical transmission of the lens of the camera before obtaining the image; increasing, by the computing system, the optical transmission of the lens of the camera from the initial optical transmission level to an increased optical transmission level that is greater than the initial optical transmission level; and capturing the image while the lens of the camera has the increased optical transmission level.

  3. The method of claim 2, wherein obtaining an image requirement for an image to be captured comprises: receiving a request that specifies a high quality image is required; and determining from the request, that the image requirement is high quality.

  4. The method of claim 2, wherein obtaining an image requirement for an image to be captured comprises: receiving, from a particular application, a request for an image; and determining, from the particular application that requested the image, that the image requirement is high quality.

  5. The method of claim 4, wherein determining, from the particular application that requested the image, that the image requirement is high quality comprises: identifying the particular application; and selecting a stored image requirement that is associated with the particular application as the image requirement from among stored image requirements for multiple different applications.

  6. The method of claim 2, comprising: determining that a user is interacting with a particular application before a request to capture the image is received; and in response to determining that the user is interacting with the particular application, obtaining the image requirement.

  7. The method of claim 2, wherein increasing the optical transmission of the lens comprises: decreasing a tint of the lens.

  8. The method of claim 7, wherein decreasing a tint of the lens comprises: applying a voltage to a coating on the lens, wherein the voltage causes the coating on the lens to lighten the tint.

  9. The method of claim 2, comprising: after capturing the image, decreasing the optical transmission of the lens of the camera.

  10. The method of claim 2, comprising: obtaining an indication of an amount of ambient light from an ambient light sensor, wherein determining to increase the optical transmission of the lens of the camera before is based on the amount of ambient light indicated by the ambient light sensor.

  11. A system comprising: one or more processors and one or more storage devices storing instructions that are operable, when executed by the one or more processors, to cause the one or more processors to perform operations comprising: obtaining, by a computing system, an image requirement for an image to be captured; determining, by the computing system, that an optical transmission of a lens of a camera has an initial optical transmission level before capturing the image; determining, by the computing system based on both the image requirement for the image and the initial optical transmission level of the lens, to increase the optical transmission of the lens of the camera before obtaining the image; increasing, by the computing system, the optical transmission of the lens of the camera from the initial optical transmission level to an increased optical transmission level that is greater than the initial optical transmission level; and capturing the image while the lens of the camera has the increased optical transmission level.

  12. The system of claim 11, wherein obtaining an image requirement for an image to be captured comprises: receiving a request that specifies a high quality image is required; and determining from the request, that the image requirement is high quality.

  13. The system of claim 11, wherein obtaining an image requirement for an image to be captured comprises: receiving, from a particular application, a request for an image; and determining, from the particular application that requested the image, that the image requirement is high quality.

  14. The system of claim 13, wherein determining, from the particular application that requested the image, that the image requirement is high quality comprises: identifying the particular application; and selecting a stored image requirement that is associated with the particular application as the image requirement from among stored image requirements for multiple different applications.

  15. The system of claim 11, comprising: determining that a user is interacting with a particular application before a request to capture the image is received; and in response to determining that the user is interacting with the particular application, obtaining the image requirement.

  16. The system of claim 11, wherein increasing the optical transmission of the lens comprises: decreasing a tint of the lens.

  17. The system of claim 16, wherein decreasing a tint of the lens comprises: applying a voltage to a coating on the lens, wherein the voltage causes the coating on the lens to lighten the tint.

  18. The system of claim 11, the operations comprising: after capturing the image, decreasing the optical transmission of the lens of the camera.

  19. The system of claim 11, the operations comprising: obtaining an indication of an amount of ambient light from an ambient light sensor, wherein determining to increase the optical transmission of the lens of the camera.

  20. A non-transitory computer-readable medium storing instructions executable by one or more processors which, upon such execution, cause the one or more processors to perform operations comprising: obtaining, by a computing system, an image requirement for an image to be captured; determining, by the computing system, that an optical transmission of a lens of a camera has an initial optical transmission level before capturing the image; determining, by the computing system based on both the image requirement for the image and the initial optical transmission level of the lens, to increase the optical transmission of the lens of the camera before obtaining the image; increasing, by the computing system, the optical transmission of the lens of the camera from the initial optical transmission level to an increased optical transmission level that is greater than the initial optical transmission level; and capturing the image while the lens of the camera has the increased optical transmission level.

  21. The medium of claim 20, wherein obtaining an image requirement for an image to be captured comprises: receiving a request that specifies a high quality image is required; and determining from the request, that the image requirement is high quality.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is a continuation of U.S. application Ser. No. 16/386,326, filed Apr. 17, 2019, the contents of which are incorporated by reference herein.

BACKGROUND

[0002] Electronic devices may include cameras that can capture images. For example, smart phones include cameras that can be used to take photos.

SUMMARY

[0003] This document describes techniques, methods, systems, and other mechanisms that control optical transmission of a lens of a camera. The optical transmission of the lens of the camera may be controlled by adjusting the degree of tint of an outer lens of the camera. For example, the optical transmission of the lens may be decreased in order to darken the tint, or increased in order to lighten the tint.

[0004] Darkening the tint of the outer lens of the camera may mask the camera from view of people, or vice versa. For example, the lens of the camera may have a lower visual contrast, e.g. lower perceptual color difference, .DELTA.E as defined by the Commission on Illumination (CIE), when the tint is darker, so that the camera appears to be part of an outer casing of a device.

[0005] Similarly, lightening the tint of the outer lens of the camera may de-mask the camera from view of people. For example, the lens of the camera may have a higher visual contrast (e.g. higher perceptual color difference, .DELTA.E as defined by CIE) when the tint is lighter so that the camera appears to be more distinct from an outer casing of a device. Generally, advantages to changing the degree of visual contrast of the camera may include allowing for variable aesthetic design, making people more comfortable with having the device around them, improving image sensor performance relative to a static constant tint, or alerting people to an active sensor state.

[0006] A system may control the optical transmission of the lens based on requirements of applications that use images captured by the camera. For example, a mobile computing device may determine not to increase optical transmission when images are to be used for a real-time augmented reality application that does not need images that include a high amount of detail. In another example, the mobile computing device may increase optical transmission when images are to be used for an image capture application that does need high quality images.

[0007] Accordingly, control of the optical transmission of the lens of the camera may enable the system to ensure that images captured by the camera are of sufficient quality for applications executing on the system while changing the user-visible appearance as desired.

[0008] One innovative aspect of the subject matter described in this specification is embodied in methods that include the actions of obtaining a first image from a camera, determining that the first image does not satisfy an image requirement, in response to determining that the first image does not satisfy an image requirement, increasing an optical transmission of a lens of the camera, and obtaining a second image with the camera while the optical transmission of the lens of the camera is increased.

[0009] Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods. A system of one or more computers can be configured to perform particular operations or actions by virtue of having software, firmware, hardware, or a combination of them installed on the system that in operation causes or cause the system to perform the actions. One or more computer programs can be configured to perform particular operations or actions by virtue of including instructions that, when executed by data processing apparatus, cause the apparatus to perform the actions.

[0010] The foregoing and other embodiments can each optionally include one or more of the following features, alone or in combination. For instance, in certain aspects increasing an optical transmission of the lens includes decreasing a tint of the lens. In some aspects, decreasing a tint of the lens includes applying a voltage to a coating on the lens, where the voltage causes the coating on the lens to lighten the tint. In some implementations, determining that the first image does not satisfy an image requirement includes obtaining the image requirement from an application and determining that the image does not satisfy the image requirement obtained from the application.

[0011] In certain aspects, obtaining the image requirement from an application includes identifying the application and selecting the image requirements that are associated with the application that was identified from among image requirements stored for multiple different applications. In some aspects, obtaining the image requirement from an application includes providing the first image to an application and obtaining an indication from the application that a quality of the first image is insufficient. In some implementations, actions include obtaining an indication of an amount of ambient light from an ambient light sensor and increasing the optical transmission of the lens of the camera based on the amount of ambient light before obtaining the first image. In certain aspects, actions include after obtaining the second image, determining that the second image satisfies the image requirement and in response to determining that the second image satisfies the image requirement, decreasing the optical transmission of the lens of the camera.

[0012] In some aspects, actions include determining a current optical transmission of the lens of the camera before obtaining a third image, obtaining a second image requirement for the third image, and determining to increase the optical transmission of the lens of the camera before obtaining the third image based on the second image requirement and the current optical transmission of the lens. In some implementations, actions include determining that a user is interacting with a particular application and in response to determining that the user is interacting with the particular application, obtaining a particular image requirement for the particular application as the image requirement.

[0013] Details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

[0014] FIG. 1 is a block diagram of an example system that controls optical transmission of a lens of a camera.

[0015] FIG. 2 is a block diagram of an example system that controls optical transmission of a lens of a camera based on sensed ambient light.

[0016] FIG. 3A is a flow diagram that illustrates an example of a process of controlling optical transmission of a lens of a camera.

[0017] FIG. 3B is a flow diagram that illustrates example of another process of controlling optical transmission of a lens of a camera.

[0018] FIG. 4 is a conceptual diagram of a system that may be used to implement the systems and methods described in this document.

[0019] FIG. 5 is a block diagram of computing devices that may be used to implement the systems and methods described in this document, as either a client or as a server or plurality of servers.

[0020] Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

[0021] FIG. 1 is a block diagram of an example system 100 that controls optical transmission of a lens of a camera. The system 100 includes a mobile computing device 110 with a lens 120, a sensor 130, a processor 140, and an optical transmission controller 150. FIG. 1 illustrates how the optical transmission of the lens 120 may be controlled so that the lens 120 initially has a low optical transmission with a dark tint so the lens 120 is more masked from view of people, and then when being used to capture high quality images, the lens 120 has a high optical transmission with a light tint so the lens 120 is less masked from view of people.

[0022] The lens 120 may be made of glass or some other material through which light can transmit and be coated with a substance through which the optical transmission of the lens 120 may be controlled. For example, the lens 120 may be coated with a film of material that is dark with low optical transmission when no voltage is applied to the film and that is light with high optical transmission when a voltage is applied to the film.

[0023] In another example, the lens 120 may be coated with a film of material that is dark with low optical transmission when voltage is applied to the film and that is light with high optical transmission when no voltage is applied to the film. In yet another example, the lens 120 may be coated with a film of material that is dark with low optical transmission after a first voltage is applied to the film and that is light with high optical transmission after a second, different voltage is applied to the film.

[0024] The sensor 130 senses light directed to the sensor 130 by the lens 120 and generates an image based on the light sensed by the sensor 130. For example, the sensor 130 may be an array of photodiodes that are covered by a color filter array. As the light passes through the lens 120 to reach the sensor 130, increasing optical transmission of the lens 120 results in more light being sensed by the sensor 130. In many cases, the more light that is sensed by the sensor 130, the more details that the sensor 130 is able to sense and represent in images generated from the sensor 130.

[0025] The processor 140 receives an image from the sensor 130 and an image requirement, and provides instructions to the optical transmission controller 150 based on the image and the image requirement. For example, the processor 140 may receive an image generated when the lens 120 has a low optical transmission and an image requirement that indicates that a high quality image is needed by an application and, in response, provide, to the optical transmission controller 150, an instruction to increase the optical transmission of the lens 120.

[0026] In another example, the processor 140 may receive an image generated when the lens 120 has a low optical transmission and an image requirement that indicates that a low quality image is needed by an application and, in response, determine not to change the optical transmission of the lens 120 so the processor 140 will not instruct the optical transmission controller 150 to adjust the optical transmission of the lens 120.

[0027] The processor 140 may receive the image requirement from an application that is currently requesting an image. For example, the processor 140 may receive a request from an application that indicates “Request video stream at high quality” where “high quality” indicates that high quality images are needed.

[0028] In another example, the processor 140 may receive a request from an application that indicates “Request video stream at low quality” where “low quality” indicates that low quality images are needed. In yet another example, the processor 140 may receive a request from an application that indicates “Request video stream for augmented reality application X,” where in response to the request, the processor 140 accesses previously stored information that indicates augmented reality application X needs images of high quality.

[0029] Additionally or alternatively, the processor 140 may provide the image received by the processor 140 to an application that is requesting the image, and the application may then respond with an indication whether the image is satisfactory or is not satisfactory. For example, the processor 140 may provide the image to augmented reality application X and receive a response of “higher quality needed” or “insufficient quality” and, in response, increase optical transmission of the lens 120.

[0030] The processor 140 may determine to decrease optical transmission of the lens 120 based on determining that no applications are requesting images. For example, the processor 140 may determine that no application has requested an image within the last one second, five second, ten seconds, or some other amount of time and, in response, decrease the optical transmission. In another example, the processor 140 may determine that the application that requested the image has provided an indication that no more images are needed, in response, determine whether any other application needs images, and, in response to determining that no other application needs images, determine to decrease the optical transmission.

[0031] The processor 140 may determine an amount to decrease optical transmission based on ambient light conditions determined from an image from the sensor 130. For example, for an image that has a high average brightness that indicates high ambient light, the processor 140 may decrease the optical transmission more, and for low ambient light, the processor 140 may decrease the optical transmission less.

[0032] Based on the determination of the processor 140 whether to increase or decrease optical transmission, the processor 140 may provide a corresponding instruction to the optical transmission controller 150. For example, in response to determining to increase optical transmission, the processor 140 may provide the optical transmission controller 150 an instruction of “increase optical transmission.”

[0033] In another example, in response to determining to decrease optical transmission, the processor 140 may provide the optical transmission controller 150 an instruction of “decrease optical transmission.” In some implementations, in response to determining to maintain optical transmission, the processor 140 may not provide the optical transmission controller 150 any instructions.

[0034] The optical transmission controller 150 may receive the instruction from the processor 140 and control application of a voltage to the lens 120 based on the instructions. For example, as shown in FIG. 1, the lens 120 may be covered by a film that increases in optical transmission when a voltage is applied so that when the optical transmission controller 150 receives the instruction to increase optical transmission, the optical transmission controller 150 may begin applying voltage to the lens 120. In the example, when the optical transmission controller 150 later receives an instruction to decrease optical transmission, the optical transmission controller 150 may stop applying voltage to the lens 120.

[0035] In another example, the lens 120 may be covered by a film that decreases in optical transmission when a voltage is applied so when the optical transmission controller 150 receives the instruction to increase optical transmission, the optical transmission controller 150 may stop applying voltage to the lens 120. In the example, when the optical transmission controller 150 later receives an instruction to decrease optical transmission, the optical transmission controller 150 may begin applying voltage to the lens 120.

[0036] In yet another example, the lens 120 may be covered by a film that changes to a first optical transmission when a first voltage is applied, maintains optical transmission when no voltage is applied, and changes to a second, lower optical transmission when a second voltage is applied. In the example, when the optical transmission controller 150 receives the instruction to increase optical transmission, the optical transmission controller 150 may, in response, apply the first voltage to the lens 120. In the example, when the optical transmission controller 150 later receives an instruction to decrease optical transmission, the optical transmission controller 150 may, in response, apply the second voltage to the lens 120.

[0037] While the system 100 is described as including the lens 120, the sensor 130, the processor 140, and the optical transmission controller 150, the system 100 may include additional, fewer, or different components. For example, the optical transmission controller 150 may be combined into the processor 140.

[0038] FIG. 2 is a block diagram of an example system 200 that controls optical transmission of a lens of a camera based on sensed ambient light. In some implementations, changing the optical transmission of the lens 120 may take time so the processor 140 may change the optical transmission of the lens 120 based on ambient light even before the sensor 130 is used to capture an image. For example, the lens 120 may not lighten in tint until one, two, five, or some other number of seconds after a voltage is applied by the optical transmission controller 150. Changing the optical transmission of the lens 120 based on ambient light may reduce the amount of time needed for the lens 120 to change tint while waiting to capture an image.

[0039] The system 200 is similar to the system 100 as it also includes a mobile computing device 210 that includes the lens 120, the sensor 130, the processor 140, and the optical transmission controller 150. However, the mobile computing device 210 also includes an ambient light sensor 220.

[0040] The ambient light sensor 220 is a sensor that senses ambient light in an environment and provides an indication of the amount of sensed light to the processor 140. For example, the ambient light sensor 220 may provide a low amount of electrical current to the processor 140 that indicates to the processor 140 that low light is being sensed. In another example, the ambient light sensor 220 may provide a higher amount of electrical current to the processor 140 that indicates to the processor 140 that more light is being sensed. The ambient light sensor 220 may be an unpowered sensor that converts sensed light to electrical current where the greater the amount of sensed light the greater the electrical current.

[0041] The processor 140 receives the indication of the amount of sensed light and the image requirements, and determines whether to change optical transmission of the lens 120 based on the indication. For example, the processor 140 may receive an indication of low light from the ambient light sensor 220 and an image requirement of medium quality image and, in response, determine that as the amount of ambient light is low the optical transmission of the lens 120 should be increased so that when the sensor 130 later captures an image, the image may already satisfy the image requirements. In the example, even if the image does not satisfy the image requirements, the optical transmission of the lens 120 may need to be increased less than from a default so the system 200 may not need to wait as long for the optical transmission of the lens 120 to increase in response to voltage applied to the lens 120.

[0042] FIG. 3A is a flow diagram that illustrates an example of a process 300 of controlling optical transmission of a lens of a camera. The process 300 may be performed by one or more computing systems, such as the systems 100 or 200 shown in FIGS. 1 and 2.

[0043] The process 300 includes obtaining a first image from a camera (310). For example, the processor 140 may obtain a first image generated from the sensor 130 sensing light that is transmitted through the lens 120.

[0044] The process 300 includes determining that the first image does not satisfy an image requirement (320). For example, the processor 140 may determine that an average brightness of the first image is below a minimum required average brightness. In another example, the processor 140 may determine that the amount of details in the first image is insufficient for use by a particular application.

[0045] In some implementations, determining that the first image does not satisfy an image requirement includes obtaining the image requirement from an application and determining that the image does not satisfy the image requirement obtained from the application. For example, the processor 140 may receive a request from an augmented reality application executing on the mobile computing device 110 for an image of high quality and determine that a quality of the first image is not of high quality.

[0046] In some implementations, obtaining the image requirement from an application includes identifying the application and selecting the image requirements that are associated with the application that was identified from among image requirements stored for multiple different applications. For example, the processor 140 may receive a request from an augmented reality application executing on the mobile computing device 110 for an image, identify the request as coming from the augmented reality application, and access stored image requirements for multiple different applications to identify a particular image requirement labeled as specifying the image requirement for the augmented reality application.

[0047] In some implementations, obtaining the image requirement from an application includes providing the first image to an application and obtaining an indication from the application that the quality of the first image is insufficient. For example, the process 300 may provide the first image to the augmented reality application, the augmented reality application may determine that the first image is of too low quality to use, and, in response, the augmented reality application may provide an indication to the processor 140 that the first image is of insufficient quality.

[0048] The process 300 includes increasing an optical transmission of a lens of the camera (330). For example, the processor 140 may instruct the optical transmission controller 150 to increase optical transmission of the lens 120. In the example, the optical transmission controller 150 may cause the lens 120 to lighten in tint.

[0049] In some implementations, decreasing a tint of the lens includes applying a voltage to a coating on the lens, where the voltage causes the coating on the lens to lighten the tint. For example, the optical transmission controller 150 may apply a voltage to an electrochromic film on the lens.

[0050] The process 300 includes obtaining a second image with the camera while the optical transmission of the lens 120 of the camera is increased (340). For example, the processor 140 may obtain the second image after the optical transmission of the lens 120 is increased.

[0051] In some implementations, the process 300 includes obtaining an indication of an amount of ambient light from an ambient light sensor and increasing the optical transmission of the lens of the camera based on the amount of ambient light before obtaining the first image. For example, the processor 140 may receive an indication from the ambient light sensor 220 that the ambient light sensed is now low light instead of high light and, in response, determine to increase the optical transmission of the lens 120.

[0052] In some implementations, the process 300 includes after obtaining the second image, determining that the second image satisfies the image requirement and, in response to determining that the second image satisfies the image requirement, decreasing the optical transmission of the lens of the camera. For example, the processor 140 may determine that the second image satisfied image requirements of the augmented reality application so that no other images are needed by the augmented reality application and, in response, the processor 140 may instruct the optical transmission controller 150 to increase darkness of the tint of the lens 120.

[0053] In some implementations, the process 300 includes determining a current optical transmission of the lens of the camera before obtaining a third image, obtaining a second image requirement for the third image, and determining to increase the optical transmission of the lens of the camera before obtaining the third image based on the second image requirement and the current optical transmission of the lens. For example, the processor 140 may determine that the lens 120 is at a moderate darkness tint, obtain a requirement of high image quality, and, in response, determine to increase the optical transmission of the lens based on determining that a high image quality is likely to need a low darkness tint.

……
……
……

You may also like...