Object detection via comparison of synchronized pulsed illumination and camera imaging

A computer implemented method comprising:

• controlling a pulsed laser illumination source to illuminate a scene;
• controlling a global shutter camera to capture a sequence of images of the scene, wherein the captured sequence of images includes images that are captured without illumination of the scene by the pulsed laser illumination source and images that are captured while the scene is illuminated by the pulsed laser illumination source;
• and
• determining presence of an object in the scene based on comparison of the
• images captured without illumination of the scene and images captured with illumination of the scene,
• wherein, when capturing an image while the scene is illuminated by the pulsed laser illumination source, the pulsed laser illumination source is controlled to provide illumination during an integration time of each pixel row of the global
• shutter camera for the image and without providing the illumination during an
• entire frame period of the image, and
• wherein the pulsed laser illumination source comprises a focused diode laser array including:
• a flat surface and a spherical surface,
• a collimation lens comprising two spherical surfaces,
• two horizontal divergence lenses comprising two spherical surfaces and two cylindrical surfaces, and
• two vertical divergence lenses comprising two spherical surfaces and two cylindrical surfaces.

A computer-readable non-transitory storage medium having stored therein a program to be executed by a computer of an image processing system, the program, when executed, causing the computer to control the image processing system to at least:

• control a pulsed laser illumination source to illuminate a scene;
• control a global shutter camera to capture a sequence of images of the scene, wherein the captured sequence of images includes images that are captured without illumination of the scene by the pulsed laser illumination source and images that are captured while the scene is illuminated by the pulsed laser illumination source;
• and
• determine presence of an object in the scene based on comparison of the images captured without illumination of the scene and images captured with illumination of the scene,
• wherein, when capturing an image while the scene is illuminated by the pulsed laser illumination source, the pulsed laser illumination source is controlled to provide illumination during an integration time of each pixel row of the global shutter camera for the image and without providing the illumination during an entire frame period of the image, and
• wherein the pulsed laser illumination source comprises a focused diode laser array including:
• a flat surface and a spherical surface,
• a collimation lens comprising two spherical surfaces,
• two horizontal divergence lenses comprising two spherical surfaces and two cylindrical surfaces, and
• two vertical divergence lenses comprising two spherical surfaces and two cylindrical surfaces.

An image processing system comprising:

• a global shutter camera;
• a pulsed laser illumination source;
• and
• a processing system comprising at least one processor and memory, the processing system configured to control the image processing system to:
• control the pulsed laser illumination source to illuminate a scene;
• control the global shutter camera to capture a sequence of images of the scene, wherein the captured sequence of images includes images that are captured without illumination of the scene by the pulsed laser illumination source and images that are captured while the scene is illuminated by the pulsed laser illumination source;
• and
• determine presence of an object in the scene based on comparison of the
• images captured without illumination of the scene and images captured with illumination of the scene,
• wherein, when capturing an image while the scene is illuminated by the pulsed laser illumination source, the pulsed laser illumination source is controlled to provide illumination during an integration time of each pixel row of the global shutter camera for the image and without providing the illumination during an entire frame period of the image, and
• wherein a ratio of a number of images captured with illumination of the scene to a number of images captured without illumination of the scene is less than one half and the ratio is dynamically adjusted based on characteristics of the object in the scene.

A computer implemented method comprising:

• controlling a pulsed laser illumination source to illuminate a scene;
• controlling a global shutter camera to capture a sequence of images of the scene, wherein the captured sequence of images includes images that are captured without illumination of the scene by the pulsed laser illumination source and images that are captured while the scene is illuminated by the pulsed laser illumination source;
• and
• determining presence of an object in the scene based on comparison of the images captured without illumination of the scene and images captured with illumination of the scene,
• wherein, when capturing an image while the scene is illuminated by the pulsed laser illumination source, the pulsed laser illumination source is controlled to provide illumination during an integration time of each pixel row of the global shutter camera for the image and without providing the illumination during an entire frame period of the image, and
• wherein a ratio of a number of images captured with illumination of the scene to a number of images captured without illumination of the scene is less than one half and the ratio is dynamically adjusted based on characteristics of the object in the scene.

A computer-readable non-transitory storage medium having stored therein a program to be executed by a computer of an image processing system, the program, when executed, causing the computer to control the image processing system to at least:

• control a pulsed laser illumination source to illuminate a scene;
• control a global shutter camera to capture a sequence of images of the scene, wherein the captured sequence of images includes images that are captured without illumination of the scene by the pulsed laser illumination source and images that are captured while the scene is illuminated by the pulsed laser illumination source;
• and
• determine presence of an object in the scene based on comparison of the images captured without illumination of the scene and images captured with illumination of the scene,
• wherein, when capturing an image while the scene is illuminated by the pulsed laser illumination source, the pulsed laser illumination source is controlled to provide illumination during an integration time of each pixel row of the global shutter camera for the image and without providing the illumination during an entire frame period of the image, and
• wherein a ratio of a number of images captured with illumination of the scene to a number of images captured without illumination of the scene is less than one half and the ratio is dynamically adjusted based on characteristics of the object in the scene.