Combined code reader and digital camera using a common photodetector

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INCORPORATION BY REFERENCE

The previously identified patent applications in the section entitled Cross References to Related Applications are hereby incorporated by reference in their entirety.

BACKGROUND

1. Technical Field

This invention relates generally to digital photography and coded image reading. More particularly, the present invention relates to a modular image capture and processing system capable of capturing both photo and coded images. The system employs a common photo-detector, image processor and interface circuitry to capture and process the photo and coded images. The present invention further relates to a system for capturing a plurality of images, both photo images and coded images, displaying the plurality of captured images as directed by a user, for selectively processing the images to detect codes and for allowing a user to select one or more of the images for transfer or decoding.

2. Description of Related Art

The use of electronic equipment to capture images in a digital format is well known in the art. Digital cameras capture images and store the captured images in an electronic format for future use. Coded image capture and decoding systems capture coded images, may comprise one or two dimensional coded images, and decode the captured coded images to reveal information contained within the coded images.

Digital cameras and coded image capture and decoding systems typically each include a processing unit, memory, a user interface and at least one data link. Both coded image capture and decoding systems and digital cameras employ photo-detectors to convert focused visual images into electronic representations of the images ("captured images"). A photo-detector may comprise a single photo-sensitive element such as those used in laser scanning systems or may comprise an array of photo-sensitive elements such as charge coupled device (CCD) elements. In a typical image capture device having a CCD array, the cost of the CCD array alone typically exceeds the cost of all other components combined.

Captured image capture requirements for photo images differ significantly from those of coded images. Image framing, focus and exposure requirements in the capture of photo images depends only on a subjective evaluation by a user made after a photo image has been captured. For coded image capture, however, a captured coded image is only considered satisfactory if it can be decoded. For example, a photo image of a distant mountain having insufficient resolution to reveal a small stone at the peak often proves satisfactory to a user. However, a distant coded image must be resolvable to prove satisfactory.

Conventional digital cameras capture photo images at the initiation of a user. Typical digital cameras respond to the depression of a button by immediately capturing a single photo image. At some time thereafter (often days later), the user views the results, identifying defects in the captured photo images. Such defects may arise from: 1) a user's improper operation of the digital camera; 2) jitter introduced by the user due to human stability limitations; 3) shaking caused during the depression of the button; 4) movement of the object being photographed; or 5) digital camera limitations. No matter what the source of a defect, the user must reattempt the entire process of attempting to capture an acceptable image. In many situations, such reattempts are undesirable, if not impossible, to perform because defects are not detected until the opportunity has passed.

Upon initiation of a user, conventional coded image capture and decoding systems repeatedly capture and attempt to decode coded images until an attempt proves successful. Typically, a user directs a coded image capture and decode device at a target containing a coded image, depress a capture and decode button and hold the button until a successful decode occurs. Because decoding is performed on each captured coded image regardless of its quality, decode processing is often performed on poor quality captured coded images and non-coded images. Such futile processing wastes power which, in portable coded image capture and decoding system, detrimentally shortens battery life.

The use of service, installation and delivery personnel to conduct business at customer sites is also well known. Such personnel typically travel to a customer's site to install, repair or deliver goods or to perform other services. The retrieval of information from customers'sites relating to site characteristics is often required and performed by the personnel that travel to the customer. For example, a bakery may desire to know the size and location of shelf space which has been allocated to it at each of the retail locations that distributes its goods. The bakery may also desire pricing and shelf spacing information regarding its competitors at such the retail locations. This information may be later used to present, distribute and price produces in the locations. Conventional approaches require that the bakery's delivery personnel manually collect the information and deliver the information to the bakery for correlation and review. Similarly, in another example, service personnel may visit a customer's site and, upon analysis of the service to be performed, may need advice or information regarding how to proceed. Often times, to get such advice, one or more trips by such service personnel between a service center and the customer's site is performed to enable the carrying out of the services.

Because of the additional reporting and information gathering responsibilities, many personnel carelessly perform information gathering and retrieval tasks, often making mistakes. Others falsify information to save time, by either not having to gather the information while at a site or not even having to visit the site at all. Such carelessness and falsification occurs because both the manual gathering and delivery of such information is time-consuming and the carelessness and falsification cannot easily be detected.

Thus, there is a need in the art for a system that captures images, decodes images when appropriate, transmits images when appropriate and otherwise performs processing functions as required to retrieve and process information.

SUMMARY OF THE INVENTION

The aforementioned problems found in the art are overcome in an image capture system of the present invention which includes a photo-detector array, an alterable optical path, and a controller. The system may also include a display, a user interface, and a wireless communication link. The photo-detector, the alterable optical path, and controller are contained within a module that is connectable to a terminal or host unit. Alternatively, the terminal unit may include the display and the user interface along with a terminal processor. Other configurations are also possible.

During operation, the system periodically operates the photo-detector to capture images based upon reflected light from an illuminated object that has been focused upon the photo-detector by the alterable optical path. The controller then retrieves the captured image from the photo-detector, processes the image as required and forwards the image to the display for viewing. The periodic capture and display process occurs, for example, every second. By issuing commands, a user of the system may store an image for semi-permanent or permanent retention. This image may be retained locally in a buffer or memory or may be transmitted over a wired or wireless data link to a central location.

The image capture system may be used as a digital camera, a coded image capture and decoding system and/or as a real-time video system. Circuitry within the terminal processor or controller may be programmed to seek coded targets within a captured image, notify the user of the detection of the detected coded targets, and allow the user to select one or more of the coded targets within a captured image. The system then decodes the selected coded targets to produce information pertinent to the user of the image capture system. The system may also direct a user to reposition the system with respect to a target so that a decodable image will be captured.

The circuitry of the image capture system may be controlled to transmit images to a central location over a wired or wireless link as they are captured or retained. The images may then be permanently stored and referenced at the central location. Information relating to the images may then be received by the system and relayed to the user. Transmitted coded images may also be decoded at the central location after transfer by higher powered processing equipment. A series of captured and transmitted images may comprise a real-time video transmission.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of an image capture system of present invention shown operating in a horizontal orientation to capture and decode a coded image;

FIG. 2 is a perspective view illustrating the image capture system FIG. 1 operating in a vertical orientation to capture a photo image;

FIG. 3 is a perspective view illustrating operation of an image capture system of FIGS. 1 and 2 operating in conjunction with wireless and wired networks in accordance with the present invention;

FIG. 4a is a front view of an image capture module of the present invention with the module having a illumination reflector unit positioned in a retracted position;

FIG. 4b is a front view of the image capture module of FIG. 4a with the illumination reflector unit in an extended position to provide background illumination during capture of an image;

FIGS. 5a and 5b are rear views of the image capture module of FIGS. 4a and 4b corresponding to FIGS. 4a and 4b respectively;

FIG. 6a is a cut-away side view of the image capture module of FIGS. 4 and 5 illustrating components contained within the module;

FIG. 6b is a cut-away side view illustrating the illumination reflector of the image capture system;

FIG. 7a is a perspective view of an image capture system of the present invention operable only in a horizontal orientation, the system operating to capture and decode a coded image, to display the coded image on a display and to identify a coded target within the captured image;

FIG. 7b is a perspective view of the image capture system of FIG. 7a operating in a horizontal orientation to capture a plurality of photo images, to display the captured photo images on the display as captured and to provide a user with an opportunity to edit, purge and permanently retain images from those captured;

FIG. 7c is a perspective view of an alternate embodiment of an image capture system of the present invention which is capable of capturing both photo images and coded images in a vertical orientation, displaying images on a display as captured and allowing a user to edit and selectively decode the captured images;

FIG. 8 is a perspective view of an image capture system of the present invention illustrating independent operation of an image capture module and a terminal unit when separated;

FIG. 9 is a schematic block diagram illustrating components of an image capture system of the present invention that is capable of capturing photo images and coded images, processing the images, parsing the images, transmitting the images, and communicating with a remote location via a wireless link;

FIG. 10 is a flow diagram illustration operation of an image capture module of the present invention during the capture of images, selectively illuminating a target, the storage of images and the transfer of images to a host unit;

FIG. 11 is a flow diagram illustrating operation of a host or terminal unit of the present invention during receipt of captured images from an image capture module, display of the received images, searching the received images for coded targets, storage of received images and transmission of received images to a remote location;

FIG. 12a is a perspective view illustrating an alternative embodiment of the image capture system of the present invention wherein the display of the system permits viewing and targeting of objects that are located behind the system;

FIG. 12b is a view of a bottom side of the system of FIG. 12a illustrating the location of the optics of the system;

FIG. 13a is side view of a photo and coded image capture system of the present invention for use only in a horizontal orientation;

FIG. 13b is a side view of the internal component layout of the system of FIG. 13a illustrating the use of an adjustable lens assembly;

FIG. 14a is a back view of an image capture system that captures images only in a vertical orientation when either attached or unattached to a terminal unit;

FIG. 14b is a front view of an image capture module of the system of FIG. 14a separated from the terminal unit illustrating an illumination unit, an optical opening, a view finder and controls for adjusting the optical system and photo-detector array; and

FIG. 15 is a flow diagram illustrating operation of the image capture system of the present invention during image capture, scrolling review of images and image selection for permanent retention and decoding.

DETAILED DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 illustrate an image capture system 100 of the present invention having an image capture module 102 and a terminal unit 104 (alternatively, host unit) that is capable of capturing both photo images and coded images. Because the optical requirements for capturing satisfactory photo images differ from those for capturing satisfactory coded images, the system 100 includes an alterable optical path that focuses reflected onto a common photo detector in different manners depending upon use. FIG. 1 illustrates operation of the system 100 in a horizontal orientation when capturing coded images while FIG. 2 illustrates operation of the system in a vertical orientation while capturing photo images. In the embodiment illustrated in FIGS. 1 and 2, the properties of the optical path in the horizontal orientation differ from the optical properties of the optical path in the vertical orientation. The image capture system 100 employs a common photo detector to capture images in both the horizontal orientation and the vertical orientation.

The terminal unit 104 provides a display 114, user interface 116 and additional processing capability. The display 114 allows a user to preview captured images prior to, during and immediately after capture of the images. Thus, the display 114 aids a user in aligning the image capture module 102 and adjusting its operation to capture satisfactory images. While a viewfinder 106 allows a user to align the module 102 when in the vertical orientation the display 114 provides a mechanism for aligning the module 102 when operating both in the vertical orientation and the horizontal orientation. In embodiments of the system that do not incorporate viewfinders, images displayed upon the display 114 provide the only visual indicia for system alignment and adjustment.

In operation, the system 100 may temporarily retain and display a series of captured images. Upon review of the images on the display 114, a user may decide to have the system permanently retain all or a portion of the images, have the system decode one or more of the images or have the system discard the images. The images may be permanently retained in memory in the terminal unit 104 or may be transmitted to a remote location for storage and subsequent review.

The image capture module 102 may operate either when connected to the terminal unit 104 or when separated from the terminal unit. A connector interface between the image capture module 102 and the terminal unit 104 provides bi-directional communication and control and may comprise, for example, a wired parallel or serial interface, or a wireless RF (radio frequency) or infrared interface. When using a wireless interface, the image capture module 102 interfaces with the terminal unit 104 without requiring a physical connection thereto. Alternatively, the image capture module may be incorporated within the housing of the terminal unit 104, as discussed further detail below.

The system 100 captures, displays images for review, stores images, transfers images and decodes images as directed by a user. Each of these functions may be independently controlled for the particular operational undertaking. The functions and operations of the system 100 may be categorized according to capture, display, storage, transfer and decoding. Thus, operations of the system will be discussed along these categories.

The system 100 captures images in various fashions depending upon user input and consistent with particular applications. In the case of the capture of photo images, the module 102 performs a capture cycle responsive to the depression of a capture button. A capture cycle may comprise capturing a single image, a series of images until the capture button is released, or the capture of a pre-determined number of images. The pre-determined number of images may be a defined number or may correspond to the available image storage capacity of the system 100. A duration between the capture of subsequent images may be established by a user or may be dependent upon the limitations of the system 100 itself, such as the minimum set-up time of the module 102 for capturing images.

In a single image capture mode, a user initiates a capture cycle by depressing a capture button causing the system 100 to capture and buffer a single image. The image is then displayed and the user determines whether to temporarily or permanently retain the image or to capture another image for consideration by providing corresponding input. This operation may be easily employed when a viewfinder 106 serves as a primary means for aligning the system 100. However, when a viewfinder is not available, such as in the horizontal orientation of FIG. 1, the mode would be less useful.

In a modified single image capture mode of operation, single images are captured and buffered at regular intervals. When captured, each image is displayed for review by a user. The user may determine to temporarily or permanently retain the image after viewing by providing proper input or may choose to discard the image by providing no input or providing a discard input to the device. The capture cycle is repeated at regular intervals so that the capture cycle serves to allow the user to frame a subject correctly and to adjust the system 100 as required to capture a desired image. For example, an image displayed that shows only the left half of the code 122 indicates to the user that the system 100 needs to be aligned to the right. An image showing an undersized code 122 indicates to the user to move the system 100 closer to the object 120. This mode works particularly well when the system 100 operates without a viewfinder wherein the display provides the only framing guide.

In a multi-image capture mode of operation, a plurality of images are captured and buffered during each capture cycle. An image buffer within the image capture module 102 provides temporary storage for a fixed number of captured images, perhaps "N" images. Upon capture of the N images, the N images are written into the buffer in a first-in-first-out (FIFO) fashion. When the buffer is filled, an indication is given to the terminal unit 104 or to the control circuitry of the image capture module 102. In one embodiment, the capture of images ceases when the buffer is full. However, in another embodiment, if the number of captured images overruns the storage capability of the image buffer, older images are overwritten by newer images.

After capture of a single image or a series of images, the terminal unit 104 allows the user to review the images, parse the images and select one or more of the images for permanent storage. Keypad interface 116 on the terminal unit 104 allows a unit to control the display of the images on the display 114. Upon review, the user may decide to permanently retain all, a portion of, or none of the images that were captured and temporarily retained. Permanently retaining images entails moving the selected images from the image buffer to semi-permanent storage in the terminal unit 104.

Permanent storage may also comprise storage at a location remote from the system 100. Thus, the system also includes a communication link to a remote location capable of being used to transfer images to the remote location. When initiated by a user, the system 100 transfers selected images to the location. The system 100 may receive feedback from the remote location relating to the captured images and to the capture of subsequent images. A wired or wireless link preferably links the system 100 to the remote location and facilitates the data transfers as required.

The system 100 may also decode captured coded images or otherwise operate to facilitate the decoding of coded images. In one mode of operation, the system 100 performs a full decode of the captured coded image. In another mode, the system 100 provides feedback to the user indicating the quality of the captured coded image prior to an attempted decode operation. The system 100 may also direct the user to alter a position or orientation of the system 100 with respect to an object 120 upon which a coded image 122 resides and/or to alter the optical properties of the system to capture a satisfactory image. Further, when directed, the system 100 parses captured images searching for coded targets and identifying coded targets when found. The system 100 then allows the user to select a coded target on the display 114 using the keypad 116 or another interface when more than one coded target is found. The system 100 may also transmit the coded image to a remote location for decoding should the decoding requirements be great, such as the case with two-dimensional coded images.

In another embodiment of the present invention, the system 100 prompts the user to correctly position the image capture module 102 or system 100 correctly with respect to a coded image 122 to enable a capture and decoding of the coded image 122. With the system 100 correctly positioned, the system 100 prompts the user to capture a coded image and to decode the coded image. Thus, the system 100 of the present invention provides the important benefit of only executing a decode cycle upon the capture of a sufficient coded image. By prompting for the capture and decoding only when a satisfactory capture is possible, the present invention facilitates efficient operation and reduced energy usage.

With the system 100 in the horizontal orientation as illustrated in FIG. 1, the image capture module 102 receives light reflected from a bar code 122 through a capture window 109 located on an end portion of the module 102. An optical path of the module 102 focuses the light onto a photo-detector array located within the module 102. The photo-detector array converts the light reflected from the bar code 122 into a captured image which is then processed and displayed on the display 114. Components of the system 100 executing these functions will be further described hereinafter.

Illumination reflector unit release button 107 operates to extend an illumination reflector unit to an extended position as compared to a retracted position. Battery door 110 opens to allow the image capture module 102 to receive a battery that powers its operation. Thus, the module 102 does not require power from the terminal unit 104. However, in other embodiments, the module 102 could receive primary or back up power from the terminal unit 104.

FIG. 2 illustrates operation of the image capture system 100 in a vertical orientation to capture a photo image. The requirements for capturing a decodable coded image are quite different than those required for capturing a photo image. For example, lensing system requirements for capturing photo images differ significantly from those required for capturing coded images. Thus, to minimize cost, the illustrated embodiment of the system 100 of the present invention includes a first optical path and a second optical path. One of the optical paths operates during the capture of coded images while the other optical path operates during the capture of photo images. Reflected images passing through each of the paths are captured by a common photo-detector and processed with common image processing circuitry. In the embodiment shown, a vertical orientation of the module 102 (as shown in FIG. 2) operates to capture photo images while a horizontal orientation of the module 102 (as shown in FIG. 1) operates to capture coded images. However, in other embodiments, the system could operate in a vertical orientation to capture coded images and in a horizontal orientation to capture photo images. Further, in still other embodiments, a single optical path could be provided with adjustable optics fixable in a first configuration to capture photo images and in a second configuration to capture coded images.

FIG. 2 illustrates the image capture system 100 capturing a photo image of a shelf space. As illustrated, the viewfinder 106 serves to provide guidance in aligning the system to capture an image of a shelf space. However, while the viewfinder provides for primary alignment, the display provides a final guide in determining whether to permanently capture an image of the shelf space 202. Because the illustrated application would include the transmission of images to a central location for further use at the central location, review of the captured image is required prior to its transmission. Thus, a typical sequence of events in this application would include, first attempting to capture a satisfactory image of the shelf space using the viewfinder. If, as evidenced by the captured image on the display, the image is satisfactory, the user initiates transfer of the captured image to a central location. This transfer could occur immediately after capture of the image via a wireless connection ("real-time" communication), by modem over a telephone line when a line becomes available ("batch" communication) or by another data connection. However, if the captured image is not satisfactory, as evidenced by the captured image on the display, the user initiates another image capture. This process is repeated until a satisfactory image is captured and transferred to a central location. After image capture is complete, the central location may communicate back to the system 100 instructing the user to rearrange or reorganize the shelf space 202. The system 100 therefore provides a mechanism for easily collecting information, quickly relaying the collected information, and receiving returned information. Users of the system at the central location provide feedback to the actual user of the system 100 via the video display to direct the user. Communication between the user of the system 100 and the central location may be achieved over the combination of wireless and wired links.

FIG. 3 illustrates a communication network 300 including the image capture system of FIGS. 1 and 2. Specifically, the communication network supports both batch and real-time communication between the image capture system 100 and a remote wired network 302 at a central location either directly or indirectly via a mobile access device 308. If configured for direct communication, the system 100 includes a wide area network (WAN) or cellular radio.

The wired network 302 includes a wireless access device 306 connected to a wired network backbone 304. The wireless access device 306 could be either a wireless access server providing file and processing service as well as buffering and relaying functionality or a wireless access point (only providing buffering and relaying functionality). The mobile access device 308 supports communication between a mobile unit 309 and a remote wired network 302, between the image capture system 100 and the mobile unit and between the image capture system 100 and the remote wired network 302. Alternatively, and or additionally, if so configured, the image capture system 100 may communicate directly with the wireless access device 306. Thus, the wireless network may include short range communication between the mobile unit 309 and the image capture system 100, medium range communication between the mobile unit 309 and the wireless access device 306, and longer range communication between the image capture system 100 and the wireless access device 306 depending upon the relative locations of the devices, or any combination thereof.

One or more computer systems 306 may also form part of the wired network 302. Through the wired network 302 and wireless network, the computer system 306 communicates with the mobile unit 309 and the image capture system 100. The wired network 302 may comprise a local area network or a wide area network connected by various wired or wireless links. For example, the wired network 302 may comprise a wired telephony network including a cellular telephony network. Thus, any user participating on the wired network 302 may communicate with the image capture system 100.

In operation, the image capture system 100 transfers captured photo and coded images to the mobile access device 308 which selectively processes, stores and forwards the images to the wired network 302 via the wireless access device 306. The image capture system 100 similarly transmits data relating to the captured images to the mobile access device 308 and the wired network 302. The image capture system 100 also receives information from the mobile access device 308 and the wired network 302. In one application, the image capture system 100 captures and decodes coded images and utilizes the decoded information to request information from the mobile access device 308. The request made to the mobile access device 308 may include captured images. In response, the mobile access device 308 delivers requested stored information to the system 100 and delivers the request, captured images, and related information to a user of the computer system 307 at a remote central location. After review of the information and captured images, the user of the computer system 307 initiates a transmission of instructions to the image capture system 100. The user of the image capture sys