Software Technology for Multi-mode power efficient light and gesture sensing with image sensors

Invented by Emanuele Mandelli, InVisage Technologies Inc

The InVisage Technologies Inc invention works as follows

Various embodiments include apparatuses or methods that include an image sensor. One example of an image sensor is a read-out circuit, a plurality pixel electrodes and an optically sensitive coating. The top electrical contact is designed to sense the electrical current flowing through it. Independent currents through each of the pixel electrodes cannot be sensed separately in a low-power mode. Independent currents through the plurality pixel electrodes can be detected in a second high resolution mode. Further methods and apparatuses can be found here.

Background for Multi-mode power efficient light and gesture sensing with image sensors

Mobile devices are used widely for communication, computing, social media and other purposes. These devices include both rear-facing and front facing camera systems. They are used for the capture of images. These camera systems are also input devices that allow communication between the user and the software and systems of the mobile phone. These camera systems can be used to recognize gestures that are made in time and space by the user of the device.

The mobile device’s electrical consumption is a matter of constant focus. The goal is to minimize power consumption and extend the battery’s operating life between charges. It is becoming increasingly important to reduce the electrical power used by electronic products. One way to minimize power consumption is to adjust the brightness of the display on a mobile device to ensure that it uses only the required power. Many mobile devices have sensors that adjust the brightness of the display based on ambient lighting levels. Some devices also use multiple sensors with different wavelengths to enable basic gesture recognition and proximity sensing.

Various embodiments herein allow you to use a camera system both as an image-capture device and as a gesture-recognition device while minimizing power consumption.

In some examples, the imaging array region only operates at power when it is being used in image capture proportionate to its resolution. Power is reduced when proximity detection or gesture recognition is required.

In embodiments the sensing areas reside on the same integratedcir as the imaging array.

In embodiments the sensing regions can be read using circuitry on one integrated circuit. However, this allows for lower power operation than if image array region circuitry was being used.

In embodiments the sensing areas are read using circuitry that is not on-chip. These embodiments could be called passive because they contain light-absorbing materials that are clad with electrical contacts. This allows for the transmission of electrical signals to be read out using separate low-power circuits.

Depicted at FIG. “Depicted in FIG. 1A is an embodiment the disclosed subject matter. Region 1 refers to the image sensor array upon which images are projected or registered. Additional sensing regions are Regions 2, 3, 4 and 5. Region 6 is the image circle. Specifically, region 6 shows the projection of focusing lens systems onto the plane of an image sensor. FIG. 1B.

As shown in FIGS. 1A and 1B have the additional sensing areas 2, 3, 4, 5, placed so that they are outside the rectangular image sensor area 1 but within the image circle 6.

Regions 2, 3, 4, and 5 will then be exposed to lighting that is similar in-focus to the illumination onto Region 1.

Regions 2, 3, 4, 5, may be used as light sensors in embodiments. In some embodiments, Regions 2, 3, 4 and 5 can be connected to electronic circuitry on-chip that allows for digitization of levels proportional to the duration of the illumination. These levels can be reported in the form of a digital number, DN.

In alternative embodiments, Regions 2, 3, 4 and 5 collect photocurrent into onchip charge stores that can be read using offchip electronics.

In additional embodiments, Regions 2, 3, 4 and 5 collect photocurrent which is carried off-chip to read using off-chip circuitry.

In certain embodiments, light sensing can be performed using at least one Region 2, 3, 4, 5, while very little or no electricity is drawn from Region 1. A low-power operating mode can be used to register light from a scene using the Regions 2,3, 4, 5,

In an embodiment, an illumination supply may be used to illuminate a scene. Regions 2, 3, 4, 5, and DN may be read to determine their charge or photocurrent levels in order to register light returning to the illuminated scene.

In different embodiments, IR Sub arrays could have the same or larger pixels and may use true GS. True GS is used in both examples to have an increase or maximum parallax error. FIG. FIG. 1B illustrates placement, if there’s chip area and it is more efficient to place it farther out. Each of the four IR sub-arrays may be powered by their own powering schemes so that they do not consume all the power of the main array. A third power tier in binned mode could be used to allow these sub-arrays to be used as large pixels for proximity detection applications.

Referring FIGS. “Referring to FIGS. 2A and 2B. Cameras may use a spectrally selective filter such as one that passes visible lights to the visible circle 6. An outer shell 7 ring, which is located around circle 6, may continue to receive infrared light. In certain embodiments, the sensing regions 2, 3, 4, and 5 can be placed within outershell 7 so that they receive infrared illumination. However, the majority of imaging array 1, may choose to be within the visible-receiving innercircle 6.

In embodiments, multiple, independently-powered light sensing regions are illuminated using a single optic. For example, the image sensor array represents a first independently-powered light sensing region. At least one peripheral light sensor consumes an electrical current that is substantial independent of the electrical energy of the image sensors array.

In some embodiments, a specialized IR filters could be used where its efficiency in filtering IR can decrease as the incident angles increase. This allows the IR sub arrays of the arrays to receive more IR photosns while shielding the visible main array 1. The corners of the visible sensor may be exposed to IR but can be image processed out. Corner artifacts such as lens shading are normal. FIG. FIG.

In different embodiments, IR Sub arrays could have the same or larger pixels and may use true GS. True GS is used in both examples to have an increase or maximum parallax error. FIG. FIG. 2B illustrates placement when there is sufficient chip area. Each of the four IR sub-arrays may be powered by their own powering schemes so that they do not consume all the power of the main array. A third power tier in binned mode could be used to allow these sub-arrays to be used as large pixels for proximity detection applications.

An infrared illumination source can be used to illuminate a scene, according to an embodiment. The imaging array region 1 will register visible light. Regions 2, 3, 4 and 5 will register the sum of visible light and infrared. They can be read for their DN, charge or photocurrent levels to register the light returned from the illuminated scene. The alignment marks on the image sensor circuit can be used to establish a spatial relationship with the sensing array 1. This allows for the alignment of the infrared blocking element during module assembly.

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