Abstract: An apparatus for determining the location and state of an object in an environment is disclosed. Three or more light-emitting beacons are located in the environment, and each beacon transmits a light pattern that contains information needed to identify the beacon. An optical receiver is attached to the object whose location needs to be determined. The optical receiver comprising one or more cameras images the beacons, and identifies the apparent direction from which the beacon is coming based on the pixel or pixels illuminated by the beacon. The optical receiver also decodes the light pattern transmitted by each beacon to identify it. Finally, based on knowledge of the locations of the beacons in the environment and based on the apparent directions from which the beacons appear to be coming, the optical receiver determines its location, and thus the location of the object.

Abstract: A camera configured for a predetermined environment can be made low profile in the following manner. The camera includes an image sensor that has a light sensitive portion that can sense light from the predetermined environment. A substantially opaque mask is disposed above the light sensitive portion of the image sensor and has at least one opening through which the image sensor senses light. The low profile structure of the camera can be realized with substantially transparent material disposed between the substantially opaque mask and the image sensor that has index of refraction that is greater than an index of refraction of the predetermined environment. Accordingly, light through the opening refracts as it passes through the substantially transparent material to the image sensor.

Abstract: An apparatus for determining the location and state of an object in an environment is disclosed. Three or more light-emitting beacons are located in the environment, and each beacon transmits a light pattern that contains information needed to identify the beacon. An optical receiver is attached to the object whose location needs to be determined. The optical receiver comprising one or more cameras images the beacons, and identifies the apparent direction from which the beacon is coming based on the pixel or pixels illuminated by the beacon. The optical receiver also decodes the light pattern transmitted by each beacon to identify it. Finally, based on knowledge of the locations of the beacons in the environment and based on the apparent directions from which the beacons appear to be coming, the optical receiver determines its location, and thus the location of the object.

Abstract: A camera configured for a predetermined environment can be made low profile in the following manner. The camera includes an image sensor that has a light sensitive portion that can sense light from the predetermined environment. A substantially opaque mask is disposed above the light sensitive portion of the image sensor and has at least one opening through which the image sensor senses light. The low profile structure of the camera can be realized with substantially transparent material disposed between the substantially opaque mask and the image sensor that has index of refraction that is greater than an index of refraction of the predetermined environment. Accordingly, light through the opening refracts as it passes through the substantially transparent material to the image sensor.

Abstract: Briefly, embodiments of an optical micro-sensor are described.

Abstract: A vision system for use in dark environments is disclosed. The vision system comprises photoreceptor circuits for generating photoreceptor signals, pooling mechanisms for generating pool signals, and an image processing means. The structure of the vision system is inspired from that of nocturnal flying insects. Applications are disclosed including use of the vision system on a mobile platform such as an air vehicle to enable perception and flight stability in dark environments.

Abstract: A monolithic camera configured for a predetermined environment can be made in the following manner. The camera is formed from an integrated circuit that has a light sensitive portion that can sense light from the predetermined environment. Two or more opaque masks are disposed within the oxide layer above the light sensitive pixel array of the image sensor. These opaque masks may be formed from the “metal” layers typically used for signal routing in image sensor integrated circuits. The opaque masks contain arrays of holes arranged so that for each pixel there is a clear path for light to reach the pixel from a corresponding part of the visual field. Each pixel is associated with a different set of holes that allows a different region of the predetermined environment to be observed.

Abstract: A method for reducing or removing sub-pixel displacements between images in a sequence of images is disclosed. In the first step, a set of images is acquired using a camera system. In the second step, pairwise distances are computed between every pair of images of the set of images. In the third step, the pairwise distances having the smallest values are identified. In the fourth step, “lucky” image pairs are selected from the image pairs having the smallest displacement. These “lucky” image pairs will have a substantially reduced sub-pixel jitter. In an alternative embodiment, after performing the first step and before performing the second step, the set of images are processed to remove whole pixel displacements between the images in the set of images.

Abstract: Briefly, embodiments of an optical micro-sensor are described.

Abstract: A method for providing vision based hover in place to an air vehicle is disclosed. Visual information is received using one or more image sensors on the air vehicle and based on the position of the air vehicle. A number of visual displacements is computed from the visual information. One or more motion values are computed based on the visual displacements. One or more control signals are generated based on the motion values.

Abstract: An algorithm for removing visual motion from a sequence of two or more images is disclosed. This algorithm may be performed with a camera system having an image sensor capable of downsampling the raw pixel image according to downsampling grid offset by a raw pixel amount. In a first exemplary embodiment a first and second downsampled image are grabbed at different times. Then the displacement between these downsampled images is computed. A third downsampled image is grabbed with an offset based on the displacement. The first and third downsampled images are lined up and cropped. If the camera system itself is moving, moving targets or other objects may be detected by parallax from the first and third downsampled images. In a second exemplary embodiment a block or feature is selected in the visual scene and then a first downsampled image is acquired. After a delay the motion of the block or feature is determined. A second downsampled image is acquired with an offset based on the motion of the block or feature.

Abstract: A monolithic camera configured for a predetermined environment can be made in the following manner. The camera is formed from an integrated circuit that has a light sensitive portion that can sense light from the predetermined environment. Two or more opaque masks are disposed within the oxide layer above the light sensitive pixel array of the image sensor. These opaque masks may be formed from the “metal” layers typically used for signal routing in image sensor integrated circuits. The opaque masks contain arrays of holes arranged so that for each pixel there is a clear path for light to reach the pixel from a corresponding part of the visual field. Each pixel is associated with a different set of holes that allows a different region of the predetermined environment to be observed.

Abstract: A camera configured for a predetermined environment can be made low profile in the following manner. The camera includes an image sensor that has a light sensitive portion that can sense light from the predetermined environment. A substantially opaque mask is disposed above the light sensitive portion of the image sensor and has at least one opening through which the image sensor senses light. The low profile structure of the camera can be realized with substantially transparent material disposed between the substantially opaque mask and the image sensor that has index of refraction that is greater than an index of refraction of the predetermined environment. Accordingly, light through the opening refracts as it passes through the substantially transparent material to the image sensor.

Abstract: An optical flow sensor is presented that directly measures the translational component of the optical flow experienced by the sensor while it is on a moving platform. The translational optical flow is measured by using a gyro to measure the platform's angular rates and then incorporating these angular rates in the optical flow computations in a manner that bypasses lags in the optical flow sensor measurement. In one embodiment, individual “velocity report” optical flow measurements have their rotational component removed before these velocity reports are utilized in the remainder of the optical flow algorithm. In another embodiment, a movable window and shifting techniques are used to form a windowed image that has no rotational optical flow components. In another embodiment, an optical flow sensor is mounted on a gimbal and held to point in one direction even as the platform on which the optical flow sensor is mounted moves.

Abstract: An optical flow sensor is presented that directly measures the translational component of the optical flow experienced by the sensor while it is on a moving platform. A prior art method of measuring translational optical flow is to simply subtract angular rates as measured by a gyro form the optical flow measurements. However this method produces noisy translational optical flow measurements resulting from lags between the gyro measurement and the optical flow measurement. In the teachings herein, translational optical flow is measured by using a gyro to measure the platform's angular rates and then incorporating these angular rates in the optical flow computations in a manner that bypasses lags in the optical flow sensor measurement. In one embodiment, individual “velocity report” optical flow measurements have their rotational component removed before these velocity reports are utilized in the remainder of the optical flow algorithm.