System and method for control of dimmable electro-optic elements based on ambient light determined by image analysis

Abstract

A system is provided for controlling a dimmable optical element for a vehicle. The system including: a dimmable optical element disposed in the vehicle, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images; and a controller communicatively connected to the electro-optic element and the image sensor. The controller is configured to: identify one or more point sources of light in one or more images captured by the image sensor; determine an ambient light level excluding light from at least one of the identified point sources of light; and vary the dimming of the electro-optic element based, at least in part, on the determined ambient light level.

Description

SYSTEM AND METHOD FOR CONTROL OF DIMMABLE ELECTRO-OPTIC ELEMENTS BASED ON AMBIENT LIGHT DETERMINED BY IMAGE ANALYSISCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority under 35 U.S.C. §119(e) upon U.S. Provisional Patent Application No. 63 / 674,388, entitled "SYSTEM AND METHOD FOR CONTROL OF DIMMABLE ELECTRO-OPTIC ELEMENTS BASED ON AMBIENT LIGHT DETERMINED BY IMAGE ANALYSIS" filed on July 23, 2024, by Keith W. Bigoness et al., the entire disclosure of which is incorporated herein by reference.TECHNOLOGICAL FIELD

[0002] The present invention relates to a system and method for controlling dimmable electro-optic elements of a vehicle and, more particularly, relates to a system and method for controlling the dimming of electro-optic elements of a vehicle based, in part, on captured images.SUMMARY OF THE INVENTION

[0003] According to one aspect of the invention, a system is provided for controlling a dimmable optical element for a vehicle. The system including: a dimmable optical element disposed in the vehicle, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images; and a controller communicatively connected to the electro-optic element and the image sensor. The controller is configured to: identify one or more point sources of light in one or more images captured by the image sensor; determine an ambient light level excluding light from at least one of the identified point sources of light; and vary the dimming of the electro-optic element based, at least in part, on the determined ambient light level.

[0004] It is another aspect of the present disclosure to provide a method for varying dimming of a dimmable optical element of a vehicle using a controller and an image sensor. The method includes using the controller to execute the steps of: identifying one or more point sources of light in one or more images captured by the image sensor; determining an ambient light level excluding light from at least one of the identified point sources oflight; and varying the dimming of the dimmable optical element based, at least in part, on the determined ambient light level.

[0005] It is another aspect of the present disclosure to provide a system for controlling a dimmable optical element for a vehicle. The system includes: a dimmable optical element disposed in the vehicle, the dimmable element including at least one of a visor, a window, and a sunroof, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images of a scene forward of the vehicle; and a controller communicatively connected to the electrooptic element and the image sensor. The controller is configured to: determine an ambient light level from the images captured by the image sensor; vary the dimming of the electrooptic element based, at least in part, on the determined ambient light level; analyze the images captured by the image sensor to detect the presence of a tunnel forward of the vehicle; and when the controller detects the presence of a tunnel, the controller compensates the current ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel such that the dimmable optical element may begin to transition to a high transmittance state prior to entering the tunnel.

[0006] It is another aspect of the present disclosure to provide a system for controlling a plurality of dimmable windows of a vehicle. The system includes: a plurality of windows disposed in the vehicle, each of the plurality of windows including an electro-optic element having variable dimming; a first image sensor associated with the vehicle to capture images of a scene in a first direction of the vehicle; a second image sensor associated with the vehicle to capture images of a scene in a second direction of the vehicle that is different from the first direction; and a controller communicatively connected to the electro-optic element of each of the plurality of windows, and the first and second image sensors. The controller configured to: determine a first ambient light level from the images captured by the first image sensor; determine a second ambient light level from the images captured by the second image sensor; compare the first and second ambient light levels to determine a sunset / sunrise condition when a difference between the first and second ambient light levels exceeds a threshold; and vary the dimming of the electro-optic element based, at least in part, on the determined first and second ambient light levels, wherein the controller dims a subset of the plurality of windows in the direction of thesunset / sunrise such that the subset has a lower transmittance than a remainder of the plurality of windows.

[0007] These and other features, advantages, and objects of the present device will be further understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The embodiments will now be described with reference to the following drawings, in which:

[0009] FIG. 1 is a plan view of a vehicle having dimmable electro-optic elements;

[0010] FIG. 2 is an electrical circuit diagram in block form illustrating a dimmable element control system implemented in the vehicle shown in FIG. 1;

[0011] FIG. 3 is an example of a field of view of an image sensor of the dimmable element control system shown in FIGS. 1 and 2;

[0012] FIG. 4 is a projected view of an interior rearview mirror assembly of the vehicle system shown in FIG. 1; and

[0013] FIG. 5 is a flow chart of a method that may be performed using the circuit shown in FIG. 2.

[0014] The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles described herein.DETAILED DESCRIPTION OF EMBODIMENTS

[0015] For purposes of description herein, the terms "upper," "lower," "right," "left," "rear," "front," "vertical," "horizontal," and derivatives thereof shall relate to the rearview assembly as oriented in FIG. 4. Unless stated otherwise, the term "front" shall refer to the surface of the element closer to an intended viewer of the rearview mirror assembly, and the term "rear" shall refer to the surface of the element further from the intended viewer of the rearview mirror assembly. However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings and described in the following specification are simply exemplaryembodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.

[0016] The terms "including," "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element preceded by "comprises a . . ." does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0017] As defined herein, "approximately" and "about," when used in reference to angles, proportions, and the like, may, in some embodiments, mean within plus or minus ten percent of the stated value. In other embodiments, "approximately" and "about," when used in reference to angles, proportions, and the like, may mean within plus or minus five percent of the stated value. In further embodiments, "approximately" and "about," when used in reference to angles, proportions, and the like, may mean within plus or minus three percent of the stated value. In yet other embodiments, "approximately" and "about," when used with reference to angles, proportions, and the like, may mean within plus or minus one percent of the stated value.

[0018] Current vehicles may include one or more dimmable electro-optic elements such as rearview mirror elements, visors, sunroofs, and windows. Such dimmable elements may be dimmed based, at least in part, on a detected ambient light level in which the vehicle is operated. For visors, sunroofs, and windows, these elements are typically dimmed in response to high ambient light levels (daytime conditions). On the other hand, rearview mirror elements are typically dimmed during nighttime conditions when ambient light levels are low and excessive glare light is detected from headlights of following vehicles to reduce the glare reflected towards the eyes of the driver. Traditionally, a dedicated discrete light sensor is used to sense the ambient light forward of the vehicle. Examples of rearview mirror assemblies having such discrete ambient light sensors are disclosed in commonly-assigned U.S. Patent No. 6,831,268, the entire disclosure of which is incorporated herein by reference. With such a discrete ambient light sensor, a sum total of the light level within the field of view is used. Thus, when driving at nighttime in a cityor other location where many point sources of light such as streetlights or other vehicles are present, the discrete ambient light sensor may incorrectly output a signal indicating that the ambient light level is higher than it actually is and thus the system may incorrectly determine that it is daytime when it is actually nighttime.

[0019] The system and method described below uses an image sensor and image analysis to detect the ambient light level and can distinguish between light detected from point sources of light and natural light. Further, the system may be able to detect sunsets, twilight conditions, and tunnels, which can otherwise present problems to ambient light detection using traditional detection methods.

[0020] FIG. 1 illustrates a vehicle 10 that may include any one or more dimmable optical elements in the form of one or more variable reflectance mirror assemblies 12, a visor 14, a sunroof 16, and windows 18. The vehicle 10 is equipped with a system 5 (FIG. 2) for controlling the dimming of the dimmable optical element(s). As explained in more detail below, the system 5 includes at least one image sensor 36 and a controller 50. Each of the dimmable optical elements may include an electro-optic element that is dimmable.

[0021] The image sensor(s) 36 are associated with the vehicle to capture images of a scene exterior to the vehicle. The scene may be a forward scene or a rearward scene. Both a forward and rearward scene may be imaged using two or more image sensors 36. A rearward scene may include a portion of the interior of the vehicle such as the region of the driver of the vehicle as well as a portion of the exterior of the vehicle as discussed further below.

[0022] Variable reflectance mirror assemblies 12 may include any mirror operable to vary the degree to which light is reflected. The reflectance of a mirror is the ratio of light reflected therefrom with respect to the light incident thereto. Further, variable reflectance mirror assemblies 12 may each be operable to provide a driver with a view of a rearward scene to the rear of the vehicle 10. Variable reflectance mirror assemblies 12 may be located inside or outside vehicle 10. For example, variable reflectance mirror assembly 12 may be an inside rearview mirror assembly 12a or an outside rearview mirror assembly such as a driver-side rearview mirror assembly 12b or a passenger-side rearview mirror assembly 12c.

[0023] The controller 50 is coupled to the image sensor 36 and the electro-optic element(s) of the dimmable element(s). The controller 50 may be configured to: identifyone or more point sources of light in one or more images captured by the image sensor 36, determine an ambient light level excluding light from any identified point sources of light; and vary the dimming of the electro-optic element based, at least in part, on the determined ambient light level.

[0024] FIG. 3 shows an example of an image 100 captured by the image sensor 36 at nighttime where one or more point sources of light 115 and 118 are present. In this example, the point sources of light 115 are overhead streetlights and the point sources of light 118 are headlamps of another vehicle. The controller 50 may be configured to detect a horizon 110 in the captured images 100 and determine the ambient light level using only light levels from a region 112 in the images 100 that is above the detected horizon 110. By looking above the horizon, light from many artificial light sources (such as headlamps 118) and roadside reflectors can be excluded from the determination of ambient light level. The controller 50 may thus identify point sources of light 115 and exclude the light from at least one, some, or all of those light sources 115 from the determination of ambient light. Thus, when driving at nighttime in a city or other location where many point sources of light such as streetlights or other vehicles are present, the system 5 may more accurately output a signal indicating the actual ambient light level and correctly determine that it is nighttime.

[0025] The controller 50 may take a long-term average of the pixel values within region 112 (excluding the pixels imaging at least one of the point sources of light 115) to determine the ambient light level. This helps to avoid the impact of quickly changing light levels.

[0026] The controller 50 may optionally be configured to analyze the images captured by the image sensor 36 to detect the presence of a tunnel forward of the vehicle 10. When the controller 50 detects the presence of a tunnel, the controller compensates the current ambient light level in anticipation of an ambient light level within the tunnel prior to entering the tunnel. Thus, the visor 14, the sunroof 16, and the windows 18 may begin to transition to high transmittance states prior to entering the tunnel while taking into account the time that it may take for these dimmable optical elements to clear.

[0027] In situations where an image sensor 36 is capturing images of a sunset or sunrise with the sun either directly within the images or otherwise influencing one image more than another image while being outside the field of view, it may be useful to compare the ambient light level determination from those images with an ambient light leveldetermination from another image sensor facing the opposite direction. If one ambient light level is much higher than another, a determination may be made of the sunset / sunrise. In this case, some windows 18 in the direction of the sunset may be dimmed whereas others may be cleared.

[0028] The controller 50 may be configured to identify and classify point sources of light 115 and to detect tunnels and sunsets using machine learning (artificial intelligence). Specifically, image data may be collected where the desired answer is known (ambient light at a particular level) and the input data is selected for having known problem conditions or expected problem conditions, and then one of several different training methods and models are used to come up with the logic for discriminating point light sources based on those input scenes that can be used on future images. For example, tunnel scenes or scenes with low ambient light levels but with many point sources of light may be used to train the system to accurately detect natural ambient light levels.

[0029] Tunnel detection can be difficult because of the combination of low intensity and high intensity light in different spatial configurations, which is difficult to program. Whereas machine learning, when given those tunnel configurations, can make inferences independent of the different configurations, and may accurately identify approaching tunnels.

[0030] Where the average brightness is the same whether it is a sunset, twilight, or lots of bright light sources in a dark scene, traditional methods would not be able to distinguish between such scenes. However, machine learning can discriminate on a higher order to better distinguish between the scenes.

[0031] Referring back to FIG. 2, the system 5 may further include a vehicle bus interface 54 for allowing communication between the controller 50 and other components via a vehicle bus 60. Such other components may be the afore-mentioned dimmable optical elements such as the outside electro-optic mirror elements 12b and 12c, the electro-optic visor element 14, the electro-optic sunroof element 16, and the electro-optic window element(s) 18. In addition, ambient light levels may be communicated to a headlamp / tail lamp control 42 for activating the headlamps and tail lamps of the vehicle 10 at nighttime or changing their operating mode from daytime running lights to nighttime lighting. Also, the ambient light levels may be communicated to a display brightness control 44 forcontrolling the brightness of one or more displays within the vehicle such that the brightness of the displays are dimmed at nighttime and brightened at daytime.

[0032] Although the entirety of the windows 18 are shown as being dimmable, it is also possible that only a portion of any given window is dimmable. For example, for the forward windshield, only a tint band may be dimmable.

[0033] In the event that the inside rearview mirror assembly 12a is a full display mirror (FDM) assembly, the brightness of the display may be controlled in response to the detected ambient light level.

[0034] Image sensor 36 may be any device operable to capture image data, comprising a pixel array. The image sensor 36 may correspond to, for example, a digital charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) active pixel sensor, although not be limited to these exemplary devices. The image sensor 36 is positioned and oriented such that it may capture image data corresponding to at least part of a forward or rearward scene. For example, image sensor 36 may be located on a vehicle 10's interior rearview mirror assembly 12a (as shown in FIG. 4), headliner, rear window, rear bumper, or trunk lid. The pixel array comprises a plurality of pixels in the form of light sensitive elements configured to measure light received through a lens or aperture. Each pixel of the pixel array may correspond to a photo sensor, an array of photo sensors, or any grouping of sensors configured to capture light. Each of the photo sensors may be operable to measure a value corresponding to a brightness or intensity of light. The image sensor 36 may have a high dynamic range. The image sensor 36 may also be a thermal camera.

[0035] Examples of rearview image sensors 36 configured to operate as high dynamic range image sensors are disclosed in U.S. Patent No. 8,289,430 entitled "HIGH DYNAMIC RANGE IMAGING DEVICE," filed December 6, 2007, by Jon H. Bechtel et al.; U.S. Patent No. 8,305,471 entitled "HIGH DYNAMIC RANGE IMAGING DEVICE," filed April 25, 2008, by Jon H. Bechtel et al.; U.S. Patent No. 8,378,284 entitled "IMAGING DEVICE," filed January 28, 2009, by Daniel Van Blerkom et al.; U.S. Patent No. 8,144,223 entitled "IMAGING DEVICE," filed January 28, 2009, by Daniel Van Blerkom et al.; U.S. Patent No. 8,629,927 entitled "IMAGING DEVICE," filed April 9, 2008, by Jon H. Bechtel et al.; U.S. Patent No. 8,587,706 entitled "IMAGING DEVICE," filed June 11, 2008, by Jon H. Bechtel; and U.S. Patent No. 9,041,838 entitled "HIGH DYNAMIC RANGE IMAGER SYSTEM," filedFebruary 14, 2013, by Jon H. Bechtel, all of which are hereby incorporated herein by reference in their entirety.

[0036] Controller 50 may be any device operable to analyze image data from the image sensor 36. For example, controller 50 may be one or more processors, a multicore processor, or any combination of processors, circuits, and peripheral processing devices. Additionally, controller 50 may comprise a memory operable to store a pixel analysis algorithm. Further, controller 50 may be operable to adjust a reflectance, brightness, transmittance, or other display characteristic of one or more dimmable optical elements.

[0037] In some embodiments, the system 5 may include a rearward facing glare light sensor 34 (FIG. 2). Glare light sensor 34 may be any device operable to sense the intensity of light in the rearward direction. Accordingly, glare light sensor 34 is communicatively connected to the controller 50. For example, glare light sensor 34 may be located on an interior rearview mirror assembly 12a.

[0038] In other embodiments, the image sensor 36 may be used to sense glare light instead of using a separate glare light sensor 34 as disclosed in commonly-assigned U.S. Patent No. 11,027,657, the entire disclosure of which is incorporated herein by reference.

[0039] To further enhance the ability of the system 5 to distinguish natural light from artificial light sources, the image sensor 36 may be an RGB-IR image sensor having pixels sensitive to Red, Green, Blue (RGB) and infrared (IR) light. An example of such an image sensor is disclosed in U.S. Provisional Application No. 63 / 613,154, entitled "SYSTEM AND METHOD FOR ESTIMATING NATURAL DAYLIGHT USING AN IMAGE SENSOR" and filed on December 21, 2023, the entire disclosure of which is incorporated herein by reference.

[0040] In some embodiments, the system 5 comprises a display 38. The display 38 may be any digital screen, such as, a light emitting diode (LED) display, organic LED display, liquid crystal display (LCD), etc. The display 38 may be communicatively connected to image sensor 36 and operable to display a view of the exterior environment outside vehicle 10. For example, the display 38 may be configured to display image data captured by the image sensor 36 to depict a rearward scene such that a driver may view the rearward scene without turning around.

[0041] In some embodiments, the image sensor 36 may be associated with the inside rearview mirror assembly 12a as shown in FIG. 4. Referring to FIGS. 2 and 4, the rearview mirror assembly 12a may include a mirror element 43 that may be an electro-optic mirrorelement 44a disposed to provide a driver of the vehicle with a view rearward relative to the vehicle. The electro-optic mirror element 44a has variable reflectivity. The electrooptic element 44a may comprise an electrochromic (EC) mirror element or a liquid crystal mirror element. In this configuration, the electro-optic element 44a may vary in reflectivity in response to a control signal from a controller 50. The control signal may change an electrical potential supplied to the electro-optic element 44a to control the reflectivity. The controller 50 selects the electrical potential to supply to the electro-optic element 44a based at least in part on the determined amount of ambient light and the detection of glare-causing light sources 118 in images 100 within a region corresponding to the field of view reflected by that mirror element to the driver's eyes.

[0042] When implemented as part of the inside rearview mirror assembly 12a, the image sensor 36 may be disposed in the bezel adjacent the electro-optic mirror element 44a or proximate a rear surface of the electro-optic assembly. If the image sensor 36 is located at the rear of the vehicle 10, it may also function as a back-up assist camera or a full-time display mirror (FDM) camera.

[0043] Although the above embodiments have been described with more specifics relating to rearview mirror assemblies, the concepts described herein may more generally be applied to any dimmable optical element of a vehicle, such as visors 14, sunroofs 16, windows 18, and the aforementioned rearview mirror assemblies 12.

[0044] In a dimmable rearview mirror assembly 12, the electro-optic element is dimmed when the ambient light level is below a threshold level and glare light is detected from a rearward scene. However, dimmable visors 14, sunroofs 16, and windows 18 are dimmed when the ambient light level is above a threshold level. This is to prevent excess sunlight from bothering the driver. The dimming of visors 14, sunroofs 16, and windows 18 may also be controlled based at least, in part, on the ambient light level, and also on further analysis of the imaged scene(s).

[0045] An example of a dimmable visor is disclosed in commonly-assigned U.S. Patent Application Publication No. US 2024 / 0131905 Al filed on October 23, 2023, by Adam R. Heintzelman et al. and entitled "SWICTHABLE VANITY MIRROR IN ELECTROCRHOMIC SUN VISOR," the entire disclosure of which is incorporated herein by reference.

[0046] A method 200 of controlling dimming of a dimmable optical element of a vehicle is illustrated in the flowchart of FIG. 5. This method 200 may be performed by the controller50 or other structures. The method 200 includes the steps of: capturing images of an exterior scene (step 202); identifying one or more point sources of light in one or more images captured by the image sensor 36 (step 204); determining an ambient light level excluding light from any identified point sources of light (step 206); and varying the dimming of the dimmable optical element based, at least in part, on the determined ambient light level (step 208).

[0047] As noted above, the image sensor 36 may be part of a driver identification and / or monitoring system 15, which is described further below. The system 15 may be operable to perform an identification function. In an exemplary embodiment, the driver identification and / or monitoring system 15 may be incorporated in the inside rearview mirror assembly 12a as shown in FIG. 4.

[0048] The driver identification and / or monitoring system 15 may be configured to process and / or control an identification function. The identification function may comprise an eye-scan or retinal identification function orfacial recognition. In this configuration, the driver identification and / or monitoring system 15 may provide for the interior rearview mirror assembly 12a to be configured to identify an operator or passenger of a vehicle based on the eye-scan or facial recognition identification functions. The identification function may be processed by the controller and / or communicated from the controller to one or more vehicle systems to provide for an identification of the operator 22 or passenger of the vehicle 10.

[0049] The eye-scan-identification function may utilize an infrared illumination of an iris of an eye for the identification. The illumination of the eye(s) may be optimized in conditions allowing for a high optical transmittance in the near infrared (NIR) range. Accordingly, the disclosure provides for a mirror element that may have a high light transmittance in wavelengths ranging from about 800 nm to 1000 nm in the optical spectrum. Additionally, in some implementations, the rearview mirror assembly 12a may comprise a plurality of light sources 41 configured to illuminate at least one iris of the operator of the vehicle.

[0050] The image sensor 36 may be configured to be able to detect light projected from at least one light source 41 that reflects back from the illuminated scene. The at least one light source 41 may correspond to one or more infrared emitters configured to output an emission 20 of light in the NIR range. In this configuration, the controller 50 may beconfigured to selectively activate the one or more infrared emitters corresponding to the at least one light source 41 to illuminate the iris, such that an identity of an operator (driver) 22 of the vehicle may be determined.

[0051] The driver identification and / or monitoring system 15 may further be used for driver and / or cabin monitoring purposes as a driver monitoring system (DMS). Such a DMS may detect whether the driver 22 appears drowsy or falls asleep while driving the vehicle. The DMS may also monitor for inattentiveness and other driver states. In addition, the DMS may monitor the presence / absence of a driver.

[0052] The infrared emitters or the light sources 41 may correspond to a plurality of infrared emitter banks. Each of the infrared emitter banks may comprise a plurality of light emitting diodes, which may be grouped in a matrix or otherwise grouped and disposed behind a rear surface of the electro-optic device. In an exemplary embodiment, the plurality of light sources 41 may correspond to a first emitter bank 24 and a second emitter bank 26. The first emitter bank 24 may be configured to output the emission in the NIR range from a first side portion 29 of a front surface 31 of the mirror element 44a. The second emitter bank 26 may be configured to output the emission in the NIR range from a second side portion 33 of the front surface 31 of the mirror element 43, which may comprise an electro-optic mirror element 44a. In this configuration, the monitoring apparatus 15 may be configured to illuminate the eyes of the operator 22, such that the image sensor 36 may capture an image of the irises of the eyes.

[0053] The image sensor 36 may be disposed on a circuit board 37, for example, a printed circuit board in communication with the controller 50. The controller 50 may further be in communication with various devices that may be incorporated in the vehicle 10 via the communication bus 60 or any other suitable communication interface 54. The controller 50 may be directly connected to the outside mirror elements 44b, 44c or may be in communication over the bus 60. The controller 50 may correspond to one or more processors or circuits, which may be configured to process image data received from the image sensor 36. In this configuration, the image data may be communicated from the image sensor 36 to the controller 50. The controller 50 may process the image data with one or more algorithms configured to determine the identity of the operator of the vehicle.

[0054] The controller 50 may further be in communication with the display 38. The display 38 may be disposed in the mirror assembly 12a behind the rear surface. Thecontroller 50 may be operable to display the image data received from the image sensor 36, such that the operator 22 may view the image data. In this configuration, the operator 22 may adjust a position of the eyes shown on the display 38 to position the eyes such that the image data may include the necessary features required to identify the operator. In an exemplary embodiment, the features required to identify the operator of the vehicle may correspond to features of the eyes of the operator 22 (e.g., the irises).

[0055] The display 38 may correspond to a partial or a full display mirror configured to display an image data through at least a portion of the mirror assembly 12a. The display 38 may be constructed utilizing various technologies, for example LCD, LED, OLED, plasma, DLP or other display technology. Examples of display assemblies that may be utilized with the present disclosure may include U.S. Patent No. 6,572,233 entitled "REARVIEW MIRROR WITH DISPLAY," U.S. Patent No. 8,237,909 entitled "VEHICULAR REARVIEW MIRROR ASSEMBLY INCLUDING INTEGRATED BACKLIGHTING FOR A LIQUID CRYSTAL DISPLAY (LCD)," U.S. Patent No. 8,411,245 entitled "MULTI-DISPLAY MIRROR SYSTEM AND METHOD FOR EXPANDED VIEW AROUND A VEHICLE," and U.S. Patent No. 8,339,526 entitled "VEHICLE REARVIEW MIRROR ASSEMBLY INCLUDING A HIGH INTENSITY DISPLAY," which are incorporated herein by reference in their entirety.

[0056] The driver identification and / or monitoring system 15 may further comprise an indicator 40 in the mirror assembly 12a. The indicator 40 may be in communication with the controller and configured to output a signal to identify a state of the eye scanning operation and / or the image sensor 36. The indicator 40 may correspond to a light source that may be operable to flash and / or change colors to communicate a state of the monitoring system 15. The indicator 40 may correspond to a light emitting diode (LED), and in an exemplary embodiment, the indicator 40 may correspond to a red, green, and blue (RGB) LED operable to identify the state of the scanning operation by outputting one of more colored emissions of light.

[0057] Variable reflectance mirror assemblies 12 may be implemented using a variety of electro-optic mirror elements 44a, 44b, 44c, such as those described in U.S. Patent No. 3,680,951 entitled "PHOTOELECTRICALLY-CONTROLLED REAR-VIEW MIRROR" to Jordan et al., and U.S. Patent No. 4,443,057 entitled "AUTOMATIC REARVIEW MIRROR FOR AUTOMOTIVE VEHICLES" to Bauer et al., each of which is incorporated herein by reference. Variable reflectance mirror assemblies 12 may be formed using liquid crystal cells as isdescribed in U.S. Patent No. 4,632,509 entitled "GLARE-SHIELDING TYPE REFLECTOR" to Ohmi et al., which is incorporated herein by reference. In an exemplary embodiment, variable reflectance mirror assemblies 12 may each be implemented as an electrochromic cell, which varies its reflectance in response to an applied control voltage, such as is described in U.S. Patent No. 4,902,108 entitled "SINGLE-COMPARTMENT, SELF-ERASING, SOLUTION PHASE ELECTROCHROMIC DEVICES, SOLUTIONS FOR USE THEREIN, AND USES THEREOF" to Byker, which is incorporated herein by reference. Electrochromic elements include an electrochromic medium having at least one solvent, at least one anodic material, and at least one cathodic material. Both of the anodic and cathodic materials are electroactive and at least one of them is electrochromic. It will be understood that regardless of its ordinary meaning, the term "electroactive" will be defined herein as a material that undergoes a modification in its oxidation state upon exposure to a particular electrical potential difference. Additionally, it will be understood that the term "electrochromic" will be defined herein, regardless of its ordinary meaning, as a material that exhibits a change in its extinction coefficient at one or more wavelengths upon exposure to a particular electrical potential difference. Electrochromic components, as described herein, include materials whose color or opacity are affected by electric current, such that when an electrical current is applied to the material, the color or opacity changes from a first phase to a second phase. The electrochromic component may be a single-layer, single-phase component, multi-layer component, or multi-phase component, as described in U.S. Patent No. 5,928,572 entitled "ELECTROCHROMIC LAYER AND DEVICES COMPRISING SAME," U.S. Patent No. 5,998,617 entitled "ELECTROCHROMIC COMPOUNDS," U.S. Patent No. 6,020,987 entitled "ELECTROCHROMIC MEDIUM CAPABLE OF PRODUCING A PRE-SELECTED COLOR," U.S. Patent No. 6,037,471 entitled "ELECTROCHROMIC COMPOUNDS," U.S. Patent No. 6,141,137 entitled "ELECTROCHROMIC MEDIA FOR PRODUCING A PRE-SELECTED COLOR," U.S. Patent No. 6,241,916 entitled "ELECTROCHROMIC SYSTEM," U.S. Patent No. 6,193,912 entitled "NEAR INFRARED-ABSORBING ELECTROCHROMIC COMPOUNDS AND DEVICES COMPRISING SAME," U.S. Patent No. 6,249,369 entitled "COUPLED ELECTROCHROMIC COMPOUNDS WITH PHOTOSTABLE DICATION OXIDATION STATES," U.S. Patent No. 6,137,620 entitled "ELECTROCHROMIC MEDIA WITH CONCENTRATION ENHANCED STABILITY, PROCESS FOR THE PREPARATION THEREOF AND USE IN ELECTROCHROMIC DEVICES," U.S. PatentNo. 6,519,072, entitled "ELECTROCHROMIC DEVICE," and International Patent Application Serial Nos. PCT / US98 / 05570 entitled "ELECTROCHROMIC POLYMERIC SOLID FILMS, MANUFACTURING ELECTROCHROMIC DEVICES USING SUCH SOLID FILMS, AND PROCESSESFOR MAKING SUCH SOLID FILMS AND DEVICES," PCT / EP98 / 03862 entitled "ELECTROCHROMIC POLYMER SYSTEM," and PCT / US98 / 05570 entitled "ELECTROCHROMIC POLYMERIC SOLID FILMS, MANUFACTURING ELECTROCHROMIC DEVICES USING SUCH SOLID FILMS, AND PROCESSES FOR MAKING SUCH SOLID FILMS AND DEVICES," which are herein incorporated by reference in their entirety. Though specific structures are disclosed for variable reflectance mirror assemblies 12, many other electrochromic devices may be used to implement variable reflectance mirror assemblies 12 without departing from the spirit of the disclosure.

[0058] According to one aspect of the present disclosure, a system is provided for controlling a dimmable optical element for a vehicle. The system including: a dimmable optical element disposed in the vehicle, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images; and a controller communicatively connected to the electrooptic element and the image sensor. The controller is configured to: identify one or more point sources of light in one or more images captured by the image sensor; determine an ambient light level excluding light from at least one of the identified point sources of light; and vary the dimming of the electro-optic element based, at least in part, on the determined ambient light level.

[0059] According to various aspects, the disclosure may implement one or more of the following features or configurations in various combinations:- wherein the dimmable optical element is one of a rearview mirror, a visor, a sunroof, and a window;- wherein the dimmable optical element is a rearview mirror, wherein the electrooptic element is dimmed when the ambient light level is below a threshold level and glare light is detected from a rearward scene whereby dimming of the electrooptic element causes a lowering of reflectance of the glare light from the rearview mirror;- wherein the dimmable optical element is a visor that is dimmed when the ambient light level is above a threshold level;- wherein the dimmable optical element is a window that is dimmed when the ambient light level is above a threshold level;- wherein the dimmable optical element is a sunroof that is dimmed when the ambient light level is above a threshold level;- wherein the controller detects a horizon in the captured images and wherein the controller determines the ambient light level using only light levels from a region in the images that is above the detected horizon;- wherein the point sources of light include streetlights; and- wherein the controller is further configured to analyze the images captured by the image sensor to detect the presence of a tunnel forward of the vehicle, when the controller detects the presence of a tunnel, it compensates the current ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel.

[0060] According to another aspect of the present disclosure, a driver monitoring system may be provided including: a dimmable optical element disposed in the vehicle, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images of a scene including at least a driver of the vehicle; and a controller communicatively connected to the electro-optic element and the image sensor. The controller is configured to: identify one or more point sources of light in one or more images captured by the image sensor; determine an ambient light level excluding light from at least one of the identified point sources of light; vary the dimming of the electro-optic element based, at least in part, on the determined ambient light level; and monitor and / or identify the driver based on images received from the image sensor.

[0061] It is another aspect of the present disclosure to provide a method for varying dimming of a dimmable optical element of a vehicle using a controller and an image sensor. The method includes using the controller to execute the steps of: identifying one or more point sources of light in one or more images captured by the image sensor; determining an ambient light level excluding light from at least one of the identified point sources of light; and varying the dimming of the dimmable optical element based, at least in part, on the determined ambient light level.

[0062] According to various aspects, the disclosure may implement one or more of the following features or configurations in various combinations:- wherein the dimmable optical element is one of a rearview mirror, a visor, a sunroof, and a window;- wherein the dimmable optical element is a rearview mirror, wherein the electrooptic element is dimmed when the ambient light level is below a threshold level and glare light is detected from a rearward scene whereby dimming of the electrooptic element causes a lowering of reflectance of the glare light from the rearview mirror;- wherein the dimmable optical element is a visor that is dimmed when the ambient light level is above a threshold level;- wherein the dimmable optical element is a window that is dimmed when the ambient light level is above a threshold level;- wherein the dimmable optical element is a sunroof that is dimmed when the ambient light level is above a threshold level;- wherein the controller detects a horizon in the captured images and wherein the controller determines the ambient light level using only light levels from a region in the images that is above the detected horizon;- wherein the point sources of light include streetlights; and- wherein the controller is further configured to analyze the images captured by the image sensor to detect the presence of a tunnel forward of the vehicle, when the controller detects the presence of a tunnel, it compensates the current ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel.

[0063] It is another aspect of the present disclosure to provide a system for controlling a dimmable optical element for a vehicle. The system includes: a dimmable optical element disposed in the vehicle, the dimmable element including at least one of a visor, a window, and a sunroof, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images of a scene forward of the vehicle; and a controller communicatively connected to the electrooptic element and the image sensor. The controller is configured to: determine an ambientlight level from the images captured by the image sensor; vary the dimming of the electrooptic element based, at least in part, on the determined ambient light level; analyze the images captured by the image sensor to detect the presence of a tunnel forward of the vehicle; and when the controller detects the presence of a tunnel, the controller compensates the current ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel such that the dimmable optical element may begin to transition to a high transmittance state prior to entering the tunnel.

[0064] According to various aspects, the disclosure may implement one or more of the following features or configurations in various combinations:- wherein the controller is further configured to identify one or more point sources of light in one or more images captured by the image sensor, wherein the controller determines the ambient light level while excluding light from at least one of the identified point sources of light; and- wherein the controller takes into account the time for the dimmable optical element to transition to the high transmittance state when determining when to begin the transition such that the dimmable optical elements are in the high transmittance state upon entering the tunnel.

[0065] It is another aspect of the present disclosure to provide a system for controlling a plurality of dimmable windows of a vehicle. The system includes: a plurality of windows disposed in the vehicle, each of the plurality of windows including an electro-optic element having variable dimming; a first image sensor associated with the vehicle to capture images of a scene in a first direction of the vehicle; a second image sensor associated with the vehicle to capture images of a scene in a second direction of the vehicle that is different from the first direction; and a controller communicatively connected to the electro-optic element of each of the plurality of windows, and the first and second image sensors. The controller configured to: determine a first ambient light level from the images captured by the first image sensor; determine a second ambient light level from the images captured by the second image sensor; compare the first and second ambient light levels to determine a sunset / sunrise condition when a difference between the first and second ambient light levels exceeds a threshold; and vary the dimming of the electro-optic element based, at least in part, on the determined first and second ambient light levels, wherein the controller dims a subset of the plurality of windows in the direction of thesunset / sunrise such that the subset has a lower transmittance than a remainder of the plurality of windows.

[0066] According to various aspects, the disclosure may implement one or more of the following features or configurations in various combinations:- wherein the controller is further configured to identify one or more point sources of light in one or more images captured by the first and second image sensors, wherein the controller determines the first and second ambient light levels while excluding light from at least one of the identified point sources of light;- wherein the first direction is forward of the vehicle and the controller is further configured to analyze the images captured by the first image sensor to detect the presence of a tunnel forward of the vehicle, and when the controller detects the presence of a tunnel, the controller compensates the first ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel such that the plurality of windows may begin to transition to a high transmittance state prior to entering the tunnel;- wherein first direction is forward of the vehicle and the second direction is rearward of the vehicle; and- wherein the system further includes a visor configured to be mounted at an upper region of the forward windshield on a driver's side of the vehicle, wherein the visor includes a visor electro-optic element having variable dimming, and wherein the controller is configured to vary the dimming of the visor electro-optic element based, at least in part, on the determined first and second ambient light level.

[0067] It will be understood by one having ordinary skill in the art that construction of the described invention and other components is not limited to any specific material. Other exemplary embodiments of the invention disclosed herein may be formed from a wide variety of materials, unless described otherwise herein.

[0068] For purposes of this disclosure, the term "coupled" (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as asingle unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated.

[0069] It is also important to note that the construction and arrangement of the elements of the invention as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and / or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and / or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations.

[0070] It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present device. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting.

[0071] It is also to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present device, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.

[0072] The above description is considered that of the illustrated embodiments only. Modifications of the device will occur to those skilled in the art and to those who make or use the device. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the device, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents.

Claims

CLAIMSWhat is claimed is:

1. A system for controlling a dimmable optical element for a vehicle, the system comprising: a dimmable optical element disposed in the vehicle, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images of a scene; and a controller communicatively connected to the electro-optic element and the image sensor, the controller configured to: identify one or more point sources of light in one or more images captured by the image sensor; determine an ambient light level excluding light from at least one of the identified point sources of light; and vary the dimming of the electro-optic element based, at least in part, on the determined ambient light level.

2. The system of claim 1, wherein the dimmable optical element is at least one of a rearview mirror, a visor, a sunroof, and a window.

3. The system of claim 1, wherein the dimmable optical element is a rearview mirror, wherein the electro-optic element is dimmed when the ambient light level is below a threshold level and glare light is detected from a rearward scene whereby dimming of the electro-optic element causes a lowering of reflectance of the glare light from the rearview mirror.

4. The system of claim 1, wherein the dimmable optical element is a visor that is dimmed when the ambient light level is above a threshold level.

5. The system of claim 1, wherein the dimmable optical element is a window that is dimmed when the ambient light level is above a threshold level.

6. The system of claim 1, wherein the dimmable optical element is a sunroof that is dimmed when the ambient light level is above a threshold level.

7. The system of any one of claims 1-6, wherein the controller detects a horizon in the captured images and wherein the controller determines the ambient light level using only light levels from a region in the images that is above the detected horizon.

8. The system of any one of claims 1-7, wherein the point sources of light include streetlights.

9. The system of any one of claims 1-8, wherein the controller is further configured to analyze the images captured by the image sensor to detect the presence of a tunnel forward of the vehicle, when the controller detects the presence of a tunnel, it compensates the current ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel.

10. A driver monitoring system comprising: the system of any one of claims 1-9 including the image sensor and the controller, wherein the controller is further configured to monitor and / or identify the driver based on images received from the image sensor.

11. A method for varying dimming of a dimmable optical element of a vehicle using a controller and an image sensor, the method comprises using the controller to execute the steps of: identifying one or more point sources of light in one or more images captured by the image sensor; determining an ambient light level excluding light from at least one of the identified point sources of light; and varying the dimming of the dimmable optical element based, at least in part, on the determined ambient light level.

12. The method of claim 11, wherein the dimmable optical element is one of a rearview mirror, a visor, a sunroof, and a window.

13. The method of claim 11, wherein the dimmable optical element is a rearview mirror, wherein the electro-optic element is dimmed when the ambient light level is below a threshold level and glare light is detected from a rearward scene whereby dimming of the electro-optic element causes a lowering of reflectance of the glare light from the rearview mirror.

14. The method of claim 11, wherein the dimmable optical element is a visor that is dimmed when the ambient light level is above a threshold level.

15. The method of claim 11, wherein the dimmable optical element is a window that is dimmed when the ambient light level is above a threshold level.

16. The method of claim 11, wherein the dimmable optical element is a sunroof that is dimmed when the ambient light level is above a threshold level.

17. The method of any one of claims 11-16, wherein the controller detects a horizon in the captured images and wherein the controller determines the ambient light level using only light levels from a region in the images that is above the detected horizon.

18. The method of any one of claims 11-17, wherein the point sources of light include streetlights.

19. The method of any one of claims 11-18, wherein the controller is further configured to analyze the images captured by the image sensor to detect the presence of a tunnel forward of the vehicle and when the controller detects the presence of a tunnel, it compensates the current ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel.

20. A system for controlling a dimmable optical element for a vehicle, the system comprising: a dimmable optical element disposed in the vehicle, the dimmable element including at least one of a visor, a window, and a sunroof, the dimmable optical element including an electro-optic element having variable dimming; an image sensor associated with the vehicle to capture images of a scene forward of the vehicle; and a controller communicatively connected to the electro-optic element and the image sensor, the controller configured to: determine an ambient light level from the images captured by the image sensor; vary the dimming of the electro-optic element based, at least in part, on the determined ambient light level; analyze the images captured by the image sensor to detect the presence of a tunnel forward of the vehicle; and when the controller detects the presence of a tunnel, the controller compensates the current ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel such that the dimmable optical element may begin to transition to a high transmittance state prior to entering the tunnel.

21. The system of claim 20, wherein the controller is further configured to identify one or more point sources of light in one or more images captured by the image sensor, wherein the controller determines the ambient light level while excluding light from at least one of the identified point sources of light.

22. The system of any one of claims 20 and 21, wherein the controller takes into account the time for the dimmable optical element to transition to the high transmittance state when determining when to begin the transition such that the dimmable optical elements are in the high transmittance state upon entering the tunnel.

23. A system for controlling a plurality of dimmable windows of a vehicle, the system comprising:a plurality of windows disposed in the vehicle, each of the plurality of windows including an electro-optic element having variable dimming; a first image sensor associated with the vehicle to capture images of a scene in a first direction of the vehicle; a second image sensor associated with the vehicle to capture images of a scene in a second direction of the vehicle that is different from the first direction; and a controller communicatively connected to the electro-optic element of each of the plurality of windows, and the first and second image sensors, the controller configured to: determine a first ambient light level from the images captured by the first image sensor; determine a second ambient light level from the images captured by the second image sensor; compare the first and second ambient light levels to determine a sunset / sunrise condition when a difference between the first and second ambient light levels exceeds a threshold; and vary the dimming of the electro-optic element based, at least in part, on the determined first and second ambient light levels, wherein the controller dims a subset of the plurality of windows in the direction of the sunset / sunrise such that the subset has a lower transmittance than a remainder of the plurality of windows.

24. The system of claim 23, wherein the controller is further configured to identify one or more point sources of light in one or more images captured by the first and second image sensors, wherein the controller determines the first and second ambient light levels while excluding light from at least one of the identified point sources of light.

25. The system of any one of claims 23 and 24, wherein the first direction is forward of the vehicle and the controller is further configured to analyze the images captured by the first image sensor to detect the presence of a tunnel forward of the vehicle, and when the controller detects the presence of a tunnel, the controller compensates the first ambient light level in anticipation of an ambient light level in the tunnel prior to entering the tunnel such that the plurality of windows may begin to transition to a high transmittance state prior to entering the tunnel.

26. The system of any one of claims 23-25, wherein first direction is forward of the vehicle and the second direction is rearward of the vehicle.

27. The system of any one of claims 23-26 and further including a visor configured to be mounted at an upper region of the forward windshield on a driver's side of the vehicle, wherein the visor includes a visor electro-optic element having variable dimming, and wherein the controller is configured to vary the dimming of the visor electro-optic element based, at least in part, on the determined first and second ambient light level.

Images