Auto-exposure for multi-imager barcode reader

A bar code reader for reading bar codes comprising:

• a housing including two or more transparent windows and defining a housing interior region so that a target object swiped or presented in relation to the transparent windows can be evaluated for a presence of a bar code;
• a plurality of cameras supported within the interior region of the housing, each camera having both an image capture sensor array for capturing an image of a bar code within an associated camera field of view and a light source for illuminating said field of view associated with said camera;
• a processing system coupled to the plurality of cameras for decoding a bar code carried by the target object from images captured by the plurality of cameras, said processor sequentially activating the light source for at least some of said cameras in synchronism with activating an exposure by the image capture sensor array to allocate different time segments within an image frame period to different cameras amongst the plurality of cameras;
• and
• a plurality of light sensors coupled to the processing system wherein each light sensor monitors a field of view of an associated camera and the processing system adjusts illumination time of the cameras based on sensed light and wherein exposure time of the sensor arrays are automatically adjusted based on a material of the windows, obtained by the bar code reader.

A bar code reader for reading bar codes comprising:

• a housing including two or more transparent windows and defining a housing interior region so that a target object swiped or presented in relation to the transparent windows can be evaluated for a presence of a bar code;
• a plurality of cameras supported within the interior region of the housing, each camera having both an image capture sensor array for capturing an image of a bar code within an associated camera field of view and a light source for illuminating said field of view associated with said camera;
• a processing system coupled to the plurality of cameras for decoding a bar code carried by the target object from images captured by the plurality of cameras, said processor sequentially activating the light source for at least some of said cameras in synchronism with activating an exposure by the image capture sensor array to allocate different time segments within an image frame period to different cameras amongst the plurality of cameras;
• wherein at least some of said plurality of cameras comprise a global shutter having an adjustable exposure time;
• and
• wherein the adjustable exposure time is adjusted based on a detected light transmissivity of the material of a window through which light passes on its way to a field of view automatically obtained by the bar code reader.

A bar code reader for reading bar codes comprising:

• a housing including two or more transparent windows and defining a housing interior region so that a target object swiped or presented in relation to the transparent windows can be evaluated for a presence of a bar code;
• a plurality of cameras supported within the interior region of the housing, each camera having both an image capture sensor array for capturing an image of a bar code within an associated camera field of view and a light source for illuminating said field of view associated with said camera;
• a processing system coupled to the plurality of cameras for decoding a bar code carried by the target object from images captured by the plurality of cameras, said processor sequentially activating the light source for at least some of said cameras in synchronism with activating an exposure by the image capture sensor array to allocate different time segments within an image frame period to different cameras amongst the plurality of cameras;
• and
• a sensor for automatically determining a characteristic of at least one window and wherein the processing system adjusts an exposure time for cameras whose field of view extends through said at least one window based on the characteristic of the at least one window which is automatically obtained by the bar code reader.

A bar code reader for reading bar codes comprising:

• a housing including two or more transparent windows and defining a housing interior region so that a target object swiped or presented in relation to the transparent windows can be evaluated for a presence of a bar code;
• a plurality of cameras supported within the interior region of the housing, each camera having both an image capture sensor array for capturing an image of a bar code within an associated camera field of view and a light source for illuminating said field of view associated with said camera;
• a processing system coupled to the plurality of cameras for decoding a bar code carried by the target object from images captured by the plurality of cameras, said processor sequentially activating the light source for at least some of said cameras in synchronism with activating an exposure by the image capture sensor array to allocate different time segments within an image frame period to different cameras amongst the plurality of cameras;
• and
• an indicia of the bar code reader, which upon being read by the barcode reader, indicates a material of said one or more windows and wherein the exposure time for the sensor arrays are automatically adjusted based on the material of the windows through which light passes on its way to the sensory array, obtained from said reading.

A method for imaging a target bar code comprising:

• providing a housing having two or more transparent windows that define a region for movement of an object having a bar code;
• positioning multiple cameras in the housing wherein each of said multiple cameras includes both an associated sensor array having a global shutter for imaging bar codes on objects outside the housing within an associated field of view and a light source for illuminating said field of view associated with said camera;
• gathering multiple images from different cameras by:
• exposing a first image from a first camera field of view as light reflected from said field of view impinges onto a first sensor array in synchronism with activating the light source associated with the first camera field of view and
• subsequent to exposing the first image, exposing other images from one or more additional camera fields of view as light reflected from said one or more additional fields of view impinges onto one or more additional sensor arrays in synchronism with activating the light source associated with each of the one or more additional camera fields of view so that the images of the cameras are obtained during a frame period of 1/30 seconds or less;
• and
• interpreting images from the cameras to determine a presence of a bar code and if present decoding the bar code, wherein an exposure time of the cameras is automatically adjusted based on window transmissivity obtained by the bar code reader reading a bar code label attached thereto.

A method for imaging a target bar code comprising:

• providing a housing having two or more transparent windows that define a region for movement of an object having a bar code;
• positioning multiple cameras in the housing wherein each of said multiple cameras includes an associated sensor array having a global shutter for imaging bar codes on objects outside the housing within an associated field of view;
• gathering multiple images from different cameras by:
• exposing a first image from a first camera field of view as light reflected from said field of view impinges onto a first sensor array;
• and
• subsequent to exposing the first image, exposing other images from one or more additional camera fields of view as light reflected from said one or more additional fields of view impinges onto one or more additional sensor arrays so that the images of the cameras are obtained during a frame period of 1/30 seconds or less;
• interpreting images from the cameras to determine a presence of a bar code and if present decoding the bar code;
• and
• wherein the cameras are adjustable exposure cameras and additionally comprising illuminating an associated field of view for each of the adjustable exposure cameras, sensing light reflected from each associated camera field of view and terminating the illumination for said associated field of view after a threshold amount of light has been reflected from said field of view and wherein an exposure time of the cameras is automatically adjusted based on window transmissivity obtained by the barcode reader.

A method for imaging a target bar code comprising:

• providing a housing having two or more transparent windows that define a region for movement of an object having a bar code;
• positioning multiple cameras in the housing wherein each of said multiple cameras includes an associated sensor array having a global shutter for imaging bar codes on objects outside the housing within an associated field of view;
• gathering multiple images from different cameras by:
• exposing a first image from a first camera field of view as light reflected from said field of view impinges onto a first sensor array;
• and
• subsequent to exposing the first image, exposing other images from one or more additional camera fields of view as light reflected from said one or more additional fields of view impinges onto one or more additional sensor arrays so that the images of the cameras are obtained during a frame period of 1/30 seconds or less;
• interpreting images from the cameras to determine a presence of a bar code and if present decoding the bar code;
• and
• positioning a plurality of light sensors for monitoring a field of view of an associated camera and adjusting an illumination time based on an amount of light reflected from the camera's field of view and wherein an exposure time of the cameras is automatically adjusted based on window transmissivity obtained by the bar code reader.

A method for imaging a target bar code comprising:

• providing a housing having two or more transparent windows that define a region for movement of an object having a bar code;
• positioning multiple cameras in the housing wherein each of said multiple cameras includes an associated sensor array having a global shutter for imaging bar codes on objects outside the housing within an associated field of view;
• gathering multiple images from different cameras by:
• exposing a first image from a first camera field of view as light reflected from said field of view impinges onto a first sensor array;
• and
• subsequent to exposing the first image, exposing other images from one or more additional camera fields of view as light reflected from said one or more additional fields of view impinges onto one or more additional sensor arrays so that the images of the cameras are obtained during a frame period of 1/30 seconds or less;
• interpreting images from the cameras to determine a presence of a bar code and if present decoding the bar code;
• and
• a sensor for automatically determining a material of at least one window and wherein the processing system adjusts an exposure time for cameras whose field of view extends through said at least one window based on the material, wherein the automatically determining a material of the window comprises automatically communicating the material to the bar code reader.

An imaging system for use in a multi-camera imaging-based bar code reader having a housing supporting a plurality of transparent windows and defining an interior region, a target object being presented near or moved with respect to the plurality of windows for imaging a target bar code on a target object, the imaging system comprising:

• a plurality of camera assemblies coupled to an image processing system, each camera assembly of the plurality of camera assemblies being positioned within the housing interior region to define a field of view which is different than a field of view of each other camera assembly of the plurality of camera assemblies, at least some of the camera assemblies including a sensor array having a global shutter for adjusting camera exposure, a light source in close proximity to the sensor array for illuminating a field of view and a light sensor for determining an amount of light reflected back to the sensor array;
• a plurality of mirrors for conveying light from a light source to a camera field of view and for returning light bouncing off a target object back to the sensor array of said camera assembly;
• and
• one or more processors for controlling image exposure of the cameras having a global shutter based upon the amount of light reflected to an associated light sensor and for evaluating images captured by said plurality of camera assemblies to determine and decode a bar code on target objects swiped through at least one camera field of view and wherein the processors are coupled to the sensors for monitoring the field of view of each of the plurality of cameras wherein the processors are operable to automatically adjust an exposure time of the cameras based on window transmissivity obtained by the bar code reader.