Electro-optical imaging reader having plural solid-state imagers with shutters to prevent concurrent exposure
A bioptical workstation includes plural image capture modules for capturing images of indicia along different fields of view. Each module includes an illuminator for illuminating the indicia with illumination light, a megapixel imager with a rolling shutter for sequentially capturing the return light, and a shutter element for passing the return light to its imager in an open state, and for blocking the return light from other modules from reaching its imager in an closed state. A controller prevents interference among the modules by controlling the shutter element to assume the open state only during a respective exposure time period during which its imager produces an electrical signal indicative of the indicia, and by controlling the shutter element to assume the closed state at all times other than the respective exposure time period to prevent capture of the return light from the other modules.
1. A reader for electro-optically reading indicia, comprising:
a housing;
a plurality of controllable image capture modules at the housing for capturing images of the indicia along different fields of view, each module including an illuminator for illuminating the indicia with illumination light, a solid-state imager with a rolling shutter for sequentially capturing return illumination light from the indicia, and a shutter element controllable between an open state and a closed state; and
a controller for preventing interference among the modules by controlling the shutter element of a respective module to assume the open state only during a respective exposure time period during which the illuminator of the respective module illuminates the indicia, and the shutter element allows the return illumination light from the illuminator of the respective module to pass to the imager of the respective module to capture the passed return illumination light and to produce an electrical signal indicative of the image of the indicia being captured, and by controlling the shutter element of the respective module to assume the closed state at all times other than the respective exposure time period to block the return illumination light from the illuminators of the other modules other than the respective module.
2. The reader of claim 1 , wherein the housing has one window located in a generally horizontal plane, and another window located in a generally upright plane that intersects the generally horizontal plane, and wherein the modules capture the return illumination light from the indicia through at least one of the windows.
3. The reader of claim 2 , wherein a first sub-plurality of the modules captures the return illumination light from the indicia through one of the windows, and wherein a second sub-plurality of the modules captures the return illumination light from the indicia through another of the windows, and wherein each sub-plurality of the modules captures the return illumination light from the indicia over the different fields of view that intersect one another.
4. The reader of claim 1 , wherein each imager is a two-dimensional array of megapixel size.
5. The reader of claim 1 , and optics within the housing for folding the return illumination light to travel along respective folded optical paths within the housing to the respective modules.
6. The reader of claim 1 , wherein each shutter element is a physical device movable between the open and the closed states, and wherein the controller is operative for moving each shutter element between the open and the closed states.
7. The reader of claim 6 , wherein the physical device is mounted on each module for pivoting movement between the open and the closed states.
8. A reader for electro-optically reading indicia, comprising:
housing means;
means including a plurality of controllable image capture modules at the housing means for capturing images of the indicia along different fields of view, each module including an illuminator means for illuminating the indicia with illumination light, a solid-state imager means with a rolling shutter for sequentially capturing return illumination light from the indicia, and a shutter means controllable between an open state and a closed state; and
means for preventing interference among the modules by controlling the shutter means of a respective module to assume the open state only during a respective exposure time period during which the illuminator means of the respective module illuminates the indicia, and the shutter means allows the return illumination light from the illuminator means of the respective module to pass to the imager means of the respective module to capture the passed return illumination light and to produce an electrical signal indicative of the image of the indicia being captured, and by controlling the shutter means of the respective module to assume the closed state at all times other than the respective exposure time period to block the return illumination light from the illuminator means of the other modules other than the respective module.
9. The reader of claim 8 , wherein each shutter means is a physical device movable between the open and the closed states, and wherein the preventing means is operative for moving each shutter means between the open and the closed states.
10. A method of electro-optically reading indicia, comprising the steps of:
capturing images of the indicia along different fields of view with a plurality of controllable image capture modules at a housing;
illuminating the indicia with illumination light by controlling an illuminator at each module;
sequentially capturing return illumination light from the indicia by controlling a solid-state imager with a rolling shutter at each module;
controlling a shutter element at each module between an open state and a closed state; and
preventing interference among the modules by controlling the shutter element of a respective module to assume the open state only during a respective exposure time period during which the illuminator of the respective module illuminates the indicia, and the shutter element allows the return illumination light from the illuminator of the respective module to pass to the imager of the respective module to capture the passed return illumination light and to produce an electrical signal indicative of the image of the indicia being captured, and by controlling the shutter element of the respective module to assume the closed state at all times other than the respective exposure time period to block the return illumination light from the illuminators of the other modules other than the respective module.
11. The method of claim 10 , and configuring the housing with one window located in a generally horizontal plane, and with another window located in a generally upright plane that intersects the generally horizontal plane, and wherein the capturing step is performed by capturing the return illumination light from the indicia through at least one of the windows.
12. The method of claim 11 , wherein the capturing step is performed by capturing the return illumination light from the indicia through one of the windows with a first sub-plurality of the modules, and through another of the windows with a second sub-plurality of the modules, and configuring the different fields of view to intersect one another.
13. The method of claim 10 , and configuring each imager as a two-dimensional array of megapixel size.
14. The method of claim 10 , and folding the return illumination light to travel along respective folded optical paths within the housing to the respective modules.
15. The method of claim 10 , and configuring each shutter element as a physical device movable between the open and the closed states, and moving each shutter element between the open and the closed states.
16. The method of claim 15 , and mounting the physical device on each module for pivoting movement between the open and the closed states.