MXPA97001398A - Reader of data form of extended work regime with reduced power consumption - Google Patents

Abstract

The present invention relates to an extended duty rate data form reader with a reduced power consumption having a camera assembly and a circuit control board including gain control circuit and exposure control circuits configured to establish an initial gain value and an initial exposure period, respectively, that result from a previous data form read session, subsequent fields of image data are captured by the camera, which are used to correct the gain and exposure relative to the initial values for gain and exposure period, thus reducing the latency period to obtain correct values and reducing the power consumption during ignition. In addition, the gain control system and the exposure control system use each open-loop feedback so that the successive fields of image data captured by the camera are used to capture correct values, thus reducing the latency time to obtain a correct value. Additionally, a reader module is provided for use in a data form reader that emulates a laser module so that the data form reader module can be easily integrated into existing laser-based data form reading systems . Preferably, the laser module emulation circuit included in the data form reader module emulates the output of a laser squaring module and a control circuit board, in which the emulation circuit is obtained as an output port. built and arranged to communicate with devices configured for use with a laser scanner

Description

FORMAT READER OF TROBA3Q EXTENDED REGIME DATA WITH REDUCED POTENTIAL CONSUMPTION CRUZODO REFERENCE OR RELATED REQUESTS This application is a continuation in part of the legal case of co-pending application No. 5651-C filed on October 26 June 1995 and Application No. 08 / 332,592, filed on October 31, 1994 and Application No. 08 / 280,489 filed on Dec. 16, 1994.

TECHNICAL COMPO The invention relates to readers of data forms and methods for reading data forms including barcodes, such as ID and 2D codes, and to other data forms such as matrix codes. More particularly, the invention relates to readers and methods of data forms that obtain high-resolution image formations of data forms with reduced power consumption.

BACKGROUND OF THE INVENTION A. Background of data forms The application and use of barcodes and well-known ßon matrix codes are growing. Bar codes and matrix codes are forms of "forms" (Jatos), which for the present purposes are defined as including all the provisions where the data is fixed in some form of readable copy by a machine. this way, the data forms include one and two dimensional barcodes (eg, UPC, Cl 28 PDF417, etc.), matrix codes (eg, Max? code? Data Matrix, Code 1) , e + c), and graphics codes, as well as words and numbers and other symbols, which may be printed or engraved on paper, plastic and metal cards and other items, data forms may be printed in ink invisible, magnetically engraved to tr-birds of magnetic tapes or magnetic ink sources, electromagnetically recorded through RF labels, stamped, tattooed (on the skin, formed by ion impurification (for semiconductor wafers) or biochemical union, etc. the use of forms of data, the originally encoded data is retrieved for later use in a variety of ways. For example, a printed bar code can be optically scanned to derive reflectance values that are digitized, stored in a volatile memory and subsequently decoded to recover the data encoded in the bar code. Regardless of the particular type of data form, an image is typically acquired and stored as pixel values for further processing. An image of a bar code or a matrix code that exists as a graphic image can be used through the use of a CCD reader, a scanner, or other suitable device, which is capable of distinguishing between values Different reflective data cells reflected by light and synchronize the data cell format for a particular data form. In this way, for example, a bar code typically consists of black-type or dark-colored elements printed on a white background area or a light color, with white spaces or a light color between the elements of the code of bars. The spaces are typically the same color as the background area, but may be a different light color in this example. In other examples the elements of a bar code or a matrix code are white or of a light color and are defined by black and dark-colored spaces and a background area. In other applications, such as engraving with l being on silicon wafers, lighting may result in a dark to light relationship in one orientation and a light to dark ratio in a different orientation. In addition to the pixel values that represent the reflective values of light ("light" is defined as spanning the entire electromagnetic spectrum for the present purposes), in other arrangements the pixel values representing the reflective values may be based on the Reflection of sound waves or other means from a data form of an appropriate configuration.

In any arrangement in which a form of data is arranged to be read in reflective values, such reflec- tive values can typically be stored as pixel values in an image memory or other storage medium in an area of bit another way which, although it is representative of the pixel values for an image, you can use any appropriate format of data storage.

B. Background of the data form reader Portable terminals of the current art with integrated laser barcode scanning modules or one-dimensional CCD barcode reader modules are not well suited for reading two-dimensional data forms. Laser barcode scanners operate by projecting a narrow laser beam, which forms a brightly lit point in the barcode. The oscillating mirrors continually redippose the laser beam so that the point moves in a sweep pattern or a tracking pattern. Generally, a sweep pattern refers to the oscillation of the beam along the horizontal e without any vertical oscillation. A tracking pattern refers to a rapid oscillation along the horizontal e and a slower oscillation along the vertical e so that the tracking pattern appears to have a sweep pattern moving up and down. A photodetector collects the lighting from the entire objective area. When the moving or flying point is incident on a highly reflective portion of the bar code, such as a white background, the light reflected from the point falls on the photosensor. When the flying spot is incident on a portion that reflects the bar code, such as a black bar, less light is reflected towards the photodetector. A laser scanner does not have to have an internal synchronization mechanism. The laser scanner calculates the relative horizontal position of the laser point based on patterns of self-synchronization known in the ID bar code. This can be referred to as a self-synchronized code system. A tracking pattern laser scanner can read a 2D barcode or PDF-.17 barcode because the PDF-417 has particular row marker patterns, which are recognizable and used by the scrutineer for vertical synchronization. This system has a very small rotation angle tolerance, because the scrutineer can not recognize a row indicator pattern or other codeword pattern unless the point slashes through the entire pattern. A laser scanner can not read 2D matrix codes like the Maxicode and the Datamatrix because such codes do not have row marker patterns for vertical synchronization. The one-dimensional CCD reader operates by forming a long and thin objective image on a one-dimensional photodetector arrangement, rather than scrutinizing a point of illumination through the bar code symbol. If the reader is positioned relative to an ID barcode such that the image of the target area formed falls relatively through the bar code, then the bar code can be decoded based on the sequences running along it. of values of gray scales derived from the pixels in which each bar and space of the code is formed as an image. Similar to the bearer scrutinizer, the ID CCD does not have a vertical synchronization and must be based on row indicator patterns for vertical synchronization. More recently, the CCD reader concept has been extended to two-dimensional CCD readers such as the TEC contact reader manufactured by the Tokyo Electric Company. A two-dimensional CCD reader forms the image of an area on a two-dimensional array of photodetectors. Such a device is capable of reading matrix codes because the two-dimensional pixel arrangement provides both horizontal and vertical synchronization. This reader is very long and bulky for practical use in a portable terminal. further, the device consumes a lot of power for portable use powered by batteries. Current two-dimensional CCD readers have an image capture system that includes a dashboard camera that continuously produces a mixed video signal representative of the target ar-ea. When a reading session begins, a portion of the video signal is selected for decoding. Because the dash camera continuously generates a video signal, it consumes approximately 1-2 watts of power. Such consumption can dry typical batteries in less than 1 hour of operation. The current image capture confi urations do not provide for the dashboard to be turned off between the reading sessions. Board cameras of the current technique require over 600 me of latency time to generate a corrected and properly exposed mixed gain video signal after being turned on. Most of the time is required to automatically adjust the gain control and the exposure period through a closed loop analogue feedback loop. Therefore, if each reading session required turning on the board camera, the reading session would be greater than 600? Ns. Due to the consumer's expectations for a quick response time, a reading session should be below 300rns. Therefore, the board camera can not be turned off between the reading sessions. The gain control systems of the current art include an analog integration circuit which receives the analog video signal from the photosensor array and generates a voltage signal. The voltage signal is input to an analog gain adjustment circuit, which adjusts the gain gauge in an appropriate manner. The closed loop logarithmic circuits require 500rns from the ignition to reach the equilibrium where a corresponding gain signal is produced. The exposure control systems of the current art also include an analog integration circuit which receives the analog video signal from the photosensor array. The output signal is input to an exposure time control circuit, which adjusts the exposure period for the sensor arrangement. The exposure control system also requires more than 500ms from the ignition to reach equilibrium and properly expose the sensor-layout. The current video camera image capture systems that include the analog integration circuit are specifically designed to eliminate any abrupt changes in the video signal, since abrupt changes are not desirable when viewed by human users. . Up to this point, the typical analog integration circuit produces a corresponding voltage signal from the received analog video signal. Therefore, there is a need to have a data form reader module based on two-dimensional images with a fast response time. There is also a need for such a reader module to have a low power consumption and to include an image capture configuration that makes it possible for the panel camera to be turned on with a small latency time so that it can be turned off between reading sessions. Moreover, there is a need for such a module to be of a size and shape comparable to current laser scanners so that it is mechanically retrofitable in devices that currently include a laser scanner. Furthermore, it is also desirable that such a reader module be electrically compatible with current laser scanners to be electrically readable in devices that currently include a laser scanner. There is also a need for a portable data collection system that includes the module for reading data forms. It is desirable that such a system be small, of light weight, has a low power consumption and overcomes other disadvantages of the devices of the prior art.

BRIEF DESCRIPTION OF THE INVENTION In accordance with this invention, a portable data form reader module with a shape and size comparable to current laser scanning modules is provided. The reader includes a dashboard camera that is turned off between the data form reading sessions to obtain a ba power consumption. To provide adequate response time, the reader in accordance with this invention includes a control circuit of < An open-loop signal that provides an initial gain setting (after power-up) equal to the gain setting stored in a memory from a previous reading session. After capturing the first image data field, the correct gain is calculated. If the gain value is used and the correct value is close, then an image field is used to decode. If it is not close, a new field is captured with the correct fixation. In any case, the most recent correct value is stored in the memory for later use. This system provides a correct gain that is obtained from 1-3 fields after the ignition that corresponds to a latency time of 50rns. Also in accordance with the invention, an open-loop exposure control system is provided. The system provides an initial exposure period equal to the exposure period stored in the memory resulting from the previous reading session. After capturing the first field of images, the correct exposure is computed, if the exposure period is used and the correct value is close, then the image field is used to decode, if it is not close, is it captured? n new field with the correct setting In any case, the most recent correct value is stored in the memory for later use.This system provides that a correct exposure is stored from 1-3 fields after the ignition corresponding to SO s of Also, in accordance with this invention, an open-loop exposure control system is provided, which fi les the period of exposure to the period used for the reading session recently on power up. In this case, the system provides an incremental adjustment so that one's own exposure can be obtained within 1 to 3 fields after power-up.Also according to this invention, the readerincludes? The long optic F # will provide a working regime of approximately 63.5 minutes and at least 215.9 minutes in front of the reader, while maintaining a wide field of vision. The reader is able to capture a high signal-to-noise ratio image in less than .01 seconds making it possible for the reader to be highly tolerant of hand-shaking. To accommodate the short and long optical exposure period F #, the reader is provided with an efficient high intensity uniform illumination module. A lighting module secured to the front surface of the reader housing to avoid the problem of lighting loss and the problem of internal reflection lighting noise associated with placing the lighting source behind a window within the reader housing. The lighting module includes a printed circuit board assembly that includes a plurality of surface mounted LEDs secured to the front side of a printed circuit board. The board is attached to a cavity in the back of a durable acrylic lens arrangement. The lens arrangement operates to direct a uniform and intense illumination towards a target area in front of the reader. In the preferred embodiment, the lighting module has an aperture in the center and the reader module is positioned to collect light reflected from the target area through the aperture. This configuration ensures that the directed illumination from the lens arrangement of the reader module is aligned with the field of view of the reader module. In? N aspect this invention, the reader module includes a circuit that emulates the output of a laser scanning module making it retrofitable in devices that currently include a laser scanner. In another aspect of this invention, a data collection system is provided that includes the reader module in accordance with this invention. The data form reading system is designed for a completely portable use and includes a wide spectrum radio, which operates to couple the reader with a computer through a compatible network (EEE 802.11). The spectrum radius can be used to transmit decoded data form data, photo image data in a compressed format, or compressed data files representing voice messages.

Also in accordance with this invention, the data reader includes user input devices such as a keyboard, screen, touch panel, microphone and a high voice that operate with several circuits to improve the functionality of the reader. . For a better understanding of the invention, together with other objects, reference is made to the appended drawings and the scope of the invention will be pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DIBU30S Preferred embodiments of the invention are described below with reference to the accompanying drawings, which are briefly described below. Figure 1 shows a perspective view of a data form reader module in accordance with this invention. Figure 2 shows a flow diagram of the operation of the open loop gain control system 25 in accordance with this invention. Figure 3 shows a flow chart of the open loop exposure control system in accordance with this invention. Figure 4 shows a diagram top view ica of the reader module in accordance with this invention.

Figure 5 shows an exploded perspective view of the lighting module of this invention. Figure 6 shows a cross-sectional view of the illumination module of this invention. Figure 7 shows a state diagram of the operation of the power control circuit according to this invention. Figure 8 shows a perspective view of a portable data collection system 10 in accordance with this invention. Figure 9 shows a perspective view of an alternative portable data collection system in accordance with this invention. Figure 10 shows a cross-sectional side view of the data form reader of Figure 8. Figure 11 shows a sectional side view of the data form reader of the Figure. . I to Figure 12 shows a block diagram of the voice mail system according to the present invention. Figure 13 shows a wireless head attachment in accordance with this invention.

DETAILED DESCRIPTION OF THE MODOLIDODE? PREFERRED This description of the invention is subject to L5 promotion of the consti tutional purposes of the US patent laws. "to promote the progress of science and useful techniques" (article 1, section 8.) The data form reader module 10 of this invention is generally shown in Figure 1. The module includes a camera assembly 26 and a decoder and control board 56. The chamber assembly 26 consists of a Parrot chamber assembly (shown as an assembly of three boards) 62, which includes a two-dimensional photo-sensing arrangement 60. The camera assembly 26 also includes an optical assembly 53 for focusing an image of a data form in a target area on the sensor array 60 and a camera housing 64 that hides the ambient light from the photosensor array 60 and positions the optical assembly 58 so that the photo sensor arrangement is substantially in the image plane. Board camera 62 includes an input port for a power signal that provides operating power to generate a mixed video signal. An additional gain input port is connected to the gain adjustment circuit to bypass the analog gain circuit and an additional exposure input port is connected to the exposure time regulation circuit to bypass the analog exposure control circuit. The control board and decoder 56 includes a digital gain control circuit, which may be in the form of a code executed by the microprocessor 51. FIG. 2 shows a flow chart of the operation of the gain control circuit. Box 200 r-e represents the initial start-up of the board chamber. Rl turn it on, the gain control circuit sets the gain value to the gain setting used during the previous data form reading session 202. The gain circuit will provide a digital value to a digital to analog converter (D / fl) , which will supply a voltage signal to the gain adjustment circuit in the board camera. The arrow 204 represents the capture of an image data field. Based on the gain value used and the resulting field of image data, a correct gain value is circulated based on an observation board at 206. The new value is stored in the memory for the next field capture at 208 If the difference between the used gain value and the calculated value is less than a threshold at 210, the field is used to decode at 212. Alternatively, if the difference is greater than the threshold, then the system returns to 202 to capture another field in the calculated value. Because the gain control system provides an initial gain setting attached to a previous correct gain setting and to incrementally adjust the gain value after evaluation of an image data field, a video signal can be obtained Corrected gain in 1-3 fields after power up. This corresponds to a latency time of 10-50rns. 1 The control board and decoder 56 also includes a digital exposure control circuit, which may be in the form of a code executed by the microprocessor. Figure 3 shows a flowchart of the operation of the exposure control circuit. The box 214 represents the initial ignition of the board camera. 01 turn it on, the exposure control circuit sets the period of exposure to the period stored in the memory of the previous data form reading session 216. The exposure control circuit will provide a digital value to a D / A converter which supplies voltage signals to the exposure adjustment circuits in the dash chamber. The box 218 represents the capture of an image data field. Based on the gain value used and the resulting field of image data, a period of correct exposure is calculated based on an observation table at 220. The new value is stored in the memory for the next field capture at 222. If the difference between the exposure period used and the calculated value is less than a threshold at 224, the field is used to decode at 226. Alternatively, if the difference is greater than the threshold, then the system returns to 216 to capture another field in the calculated value. Because the exposure control system provides an initial exposure setting attached to an exposure setting previously corrected and to incrementally adjust the exposure period after the evaluation of a data image field, a Video signal properly exposed can be obtained in 1-3 (-amps after power-on.) This corresponds to a latency time of 10-50ms Referring again to Figure 1, the control panel and decoder 56 includes image processing circuit, in the form of a code operable by the processor 53, which is operable to decode the data form in the image area, the appropriate decoder is described in the patent application of FIG. legal case No. 92100 filed on August 17, 1995 and the application for Patent of legal case No. 92115 filed on May 31, 1995 and the contents of both applications are incorporated herein by reference Other decoder systems known in the art are also contemplated by this invention. The decoded results are available for other processing circuits (mentioned below) through a data transfer link 53. The control board and decoder 56 further includes a laser module emulation circuit in the form of a code. executable by the icroprocessor 51. The emulation circuit operates to encode the decoded results in a normal one-dimensional bar code format, such as code 39, and outputs a square wave signal that emulates the square wave signal of the module laser scanner scrutinizing the one-dimensional code. It should be appreciated that this feature provides electrical compatibility with? N L9 laser scanning module while providing the ability to read a variety of data forms including two-dimensional matrix codes. When operating in a laser emulation mode, the square wave signal is made available for further processing via the data transfer link 53. In another embodiment, because the module is in the form of bytes. captures an image of the target area, the device, in addition to capturing the image of a camera (you can use it to photograph an object in the target area.) For example, an operator can use the reader module to photograph an image. Damaged product and also capture an image of an image of a damaged image When a photo image is captured, the decoding board will transfer a digital image, or a bit of the image through the link. data transfer 53. While Figure 1 shows the reader module of this invention in the form of a 26 and? n control camera assembly and a decoder board 54, Figure 14 shows a single board mode. This mode provides a much shallower module with a longer front form factor, which is useful for using the reader module in a relatively flat graphic type computer. While Figure 1 shows the reader module 10 of this invention in the form of a camera assembly 26 and a control board and decoder 56, Figure 4 shows the upper cut-away view of the camera assembly 26 with the microprocessor 51, the data transfer link 53 and associated circuits for carrying out open-loop gain control, open-loop exposure control, decoding, and other aforementioned functions integrated in the board camera assembly 62. The performance of the Data reader module is improved by providing an optical system with an extended work regime. Based on the position between the optical assembly and the photosensor arrangement, there is a better focus position S2 in front of the optical assembly 53, in which an image of the object in the field of the object 66 will be sharper in the arrangement of sensor 60. The image is gradually degraded by moving the object towards the cutting distance of the near field SI and at a far field cutting distance S3. The optical assembly 58 also has a field of view 68, which is wide enough to form images of data forms (ie long image in the far field S3 and still provide a large image of a small data structure located in the field). In the preferred embodiment, the optical assembly 58 has a working rate of from about 63.5 nm to at least 215.9 nm from the front surface of the optical assembly 86, with the best focus distance being 139.7 mm. preferred corresponds to a target surface of 127 m long by 95.25 nm wide at 215.9 from the lens surface 86.

An optical system that will satisfy these performance requirements includes a symmetric lens structure. Two substantially identical lenses 82 and 84 will be positioned with mirrored symmetry in the aperture 90. the surface 86 is spherical and has a magnitude and a shape defined as an even sphere having a radius of curvature of 1.5298 inm, a constant conic of -0.029890, a sixth order spherical deformation with? n deformation coefficient of 0.0096 mm, an eighth order coefficient of -0.0057, and a tenth order coefficient of 0.0023. The surface 88 is a spherical surface with a radius of curvature of 1.6004 nm. The opening 90, rnide 0.3606 inrn and is positioned between the lenses 82 and 84 as shown to provide the optical assembly with an F # 13. The diameter of the lens is not critical for this invention. A more detailed description of the optical system of this invention can be found in the U.S. patent application. of legal case No.565l-C filed on June 26, 1995 and assigned to the same assignee of the present invention, the contents of which are incorporated herein by reference. Because the optical assembly is used in a portable reader, it is desirable that the assembly be lightweight and impact resistant. In the preferred embodiment, the optical material used to make the lens element is plastic. A plastic optic will reduce the cost of glass equivalent eneamble by 60% and will provide a much more impact resistant system. Another benefit of plastic optics is that the costs associated with the polishing of spherical surfaces in glass optics is avoided. A spherical surface is easily formed by injection molding an optical (ie plastic) Although the above optical system provides the desired attributes of the invention, those skilled in the art are able to provide other opticals with similar performance characteristics. the desired working regime and the viewing range of the reader of this invention indicate that the optical system must have a large F # (F # 5.6 or greater), the exposure period of the photosensor array and the illuminating system for the reader to provide adequate exposure to the photosensor array To reduce the effect of manual agitation, the exposure period should be 0.1 seconds or less, which is substantially less than that of the CCD readers Therefore, the lighting system of this invention should provide adequate illumination to accommodate the large F # and a short exposure time. Equivalent to the sensor arrangement-requires an object field illumination of 0.3 lux assuming an exposure period of .03 seconds and? n F # 1.2. To determine the illumination object field of the preferred embodiment for a second exposure period of 0.01 and? N F # 13, the following formula is used:? 3 Illumination intensity) (Exposure period) = constant (l ~ #) 2 Therefore, the minimum field illumination required for the reader of this invention is 106 lux at the far field cutting distance. Referring to Figure 5, which is an exploded perspective view of the lighting module 28, it can be seen that the module 28 includes a lens arrangement 24 and a printed circuit board assembly 40, Vi board assembly printed circuit board 40 includes a plurality of surface mount LEDs 46 secured to a printed circuit board 54. Printed circuit board 54 includes printed conductors and a power cable 72 that operates to supply power to LEDs 46. An LED Suitable surface mounting is produced by Marktech Corporation of Latham, NY, as part No. MTSM735K-UR or MTSM745Kñ-UR. Each will provide a brightness of 285 rncd on a lighting field of approximately 68 °. The small form of the LED 46 provides that they be placed Twelve in a row measuring less than 38.1 RMN. The printed circuit board assembly 54 includes 24 LEDs 46 in two rows that provide 6840 rncd of uniform illumination over a 68 ° cape. The array arrangement 24 includes a plurality of exposure illuminating lens elements 30 all of which are positioned in front of an LED 46. The exposure illuminating lens 30 directs the 68 ° illumination field from each LED in a field of even smaller illumination that corresponds to the optic field of vision (approximately 50 °). With reference to Figure 6, which shows a cross-sectional view of the assembled lighting module 28, it can be seen that each exposure lens cell 30 has an inner lens surface 42 and a focal point 80. By blunting the ED 1 between the focal point 80 and the Inside surface 42, the Lens cell acts as an element that directs light, more than an image-forming element, thus avoiding hot spots in the target area and providing highly uniform illumination. The 68 ° illumination field from each LED 46 is collected by each lens cell 30 and directed in a field corresponding to the field of view of the optical system, which is less than 68 °. Furthermore, because the lens cells 30 overlap, there is "crosstalk" between the optical surfaces so that the illumination from? N LED can be directed towards the target area by a cell associated with another LED. 6840 rncd of illumination, on a field of illumination that corresponds to the field of optical vision, will provide an intensity of illumination greater than 106 lux in the distance of cut of the distant field of 216 mrn. Referring again to FIG. 5, two target selection lens elements 34 selected on two objective selection LEDs 47 project two target selection illumination beams 107, forming hot spaces in the target area at angles that they correspond to the field of view of the optical systems 68. The hot spaces are visible to the operator and facilitate the positioning of the reader of the portable data form held manually so that the form of objective data is within (Jel field of optical system view The lens arrangement 24 forms the front surface of the lighting module which protects the printed circuit board assembly 40 from physical impact, as well as dirt, moisture and other harmful elements found in the environment. therefore, the lens arrangement 24 is preferably molded from an impact resistant acrylic - another suitable material having a high capacity d of lighting transmission and durability necessary for the environment in which a manually held portable data reader is operated. To further protect the printed circuit board assembly 40 from harmful elements in the environment, an adjustable coating is applied to the board assembly 40 and the assembly is attached to a cavity in the rear of the lens assembly 24 with a cmoacrolate, a UV cure or a structural adhesive. Referring to Figures 5 and 1, the lighting module 28 can be secured to the front of the carcass housing 64 by inserting 4 screws through the four holes 57 in the reader module and screwing them into the coaxially aligned holes 59 in the camera housing 64 Given that the reader module 10 is designed for use in portable data collection systems, the module includes a power-saving circuit designed to operate with a manually activated two-position trigger. The trigger can be either a two-position trigger (released and pulled) or a three-position trigger (released, first position and second position). The circuit controls the operation of the dashboard 62 and of the module 28 to illuminate during a session, and reading Figure 7 shows a representative state diagram of the power control circuit. provides power to neither the lighting module nor the dashboard camera.When the three position trigger is pulled to the first position, the system moves towards the target selection state 230. In the target selection state, the The microprocessor provides that the target selection illuminators are turned on and the dashboard camera and exposure illuminators are turned off.When the trigger is pulled to the second position, the system enters the readout state in data form 232. The status The data form reading has two substates, exposure 234 and decode 236. In the exposure state 234, the target selection illuminators are turned off. While the exposure illuminators and the dashboard camera are operational. After capturing an image, the system enters the decoding substation in which the exposure illuminators and the dashboard camera are turned off, while the objective selection illuminators are on to help the operator hold the reader in position in case a second image needs to be captured. If successful decoding occurs, the system returns to the state (Je off 228. If the trigger is released, the system returns to the target selection state 230 and the off state 228. A timeout may also cause the system to return to the state If the system has only a two-position trigger, the system can operate in two modes: In the first mode, pulling the trigger causes the system to enter the target selection state 230. Release the trigger causes the system to enter the data form read state 234. The exposure sub-state 234 and the decoded sub-state 236 function similarly to the three-position trigger mode, a time out will cause the system to return to the off state Alternatively, pulling the trigger may cause the system to enter a fully automatic read state 238. The system will automatically enter the substate of target selection 230 for a period of time and subsequently enter into the data reading form 232. The operation of the data reading status is the same as in the aforementioned modes. The release of the trigger will cause the system to return to the off state 228. Figures 8 and 9 show two modalities of a portable data collection system in accordance with this invention. The same numbers are used to identify similar parts, the housing shown in Figure 8 is generally a gun-shaped device 11 with housing 12, which forms a top closure, and a handling portion 14 that extends through under the top closure. The housing is constructed of a suitable impact resistant plastic that provides both durability and light weight. A two-position trigger switch 16 is properly mounted and used to provide a signal to initiate a data reading session. A plurality of key switches 22 and a display screen 32 with an overlapping touch panel 44 are visible on the surface higher. The system 11 shown in Figure 9 is generally a palm-shaped shaped pair to be held in the palm of the operator's hand. A plurality of key switches on the upper surface 22 are positioned to be operated by the same hand that holds the device. Also on the top surface is a display screen 32 with an overlay touch panel 44. The housing 12 is constructed of an impact resistant plastic suitable for both durability and light weight. A multi-position trigger switch 16, to initiate the data form reading session, it is located in the center of the upper surface-to enable activation by means of the thumb of the oper- ator. Referring to FIGS. 10 and 11, which show a sectional side view of the devices of FIGS. 8 and 9 respectively, it can be seen that the camera assembly 26 is positioned within the housing immediately behind the front surface 18. The camera housing 64 projects through the opening 17 in the reader housing and the opening 36 in the lighting module. A seal (not shown) can be placed around the nose of the chamber housing 64 to create an airtight seal between the chamber housing and the reader housing 12 to prevent dirt and moisture from entering the interior of the reader housing. through the opening 17. In the preferred embodiment, the control board and decoder 56 is coupled to a main control board 31, which includes a microprocessor 13 for further processing the data transferred from the control and decoding board. to the main control board 31 via the data transfer link 53. The main control board 31 includes a serial output port coupled to a connector in the housing that operates to transfer the decoded jacks or the image data. towards a remote terminal through a connection of <; able (not shown). The connector may be a traditional pin-connector to which it is fixed-coupling-connector. Alternatively, as shown in Figure 1, the connector may be conductive contact surfaces 333 on the outside of the housing 12 which align surfaces with coupling contact when the device is placed in a fastening station. Because the data collection system of this invention is designed for portable use, a cable connection to a host computer is impractical in many situations. Therefore, the system includes a broad spectrum radio board 33 that provides a wireless link between the main control board 31 and a remote host computer. The external antenna 46 as shown in Figure 10, or the internal antenna 47 as shown in Figure 11, functions to improve reception. The broad-spectrum board 33 includes a digital and analog circuit for transmitting and receiving data in a wireless network such as an IEEE 802.11 compatible wide-band direct-sequence or broad-spectrum frequency hopping network. Due to the wide-spectrum radius, the data-form reader module conducts a significant current from a power cell 48, the radius must not operate during a data format reading session and a read session; ?? Forms of data must not start during the communication to limit the peak current conduction. Therefore, the radius and the circuits that control the form reading session (Je data provide blocking signals in each one to ensure that the power is not driven simultaneously.) The blocking signal from the radio to the reading circuit of the The data form will prevent the initiation of a read session The session will be delayed until the signal stops The blocking signal of the data form Reading circuit to the radio will prevent the radio from sending or receiving data packets. Therefore, the network transmission protocol should be such that the radio in the portable data form reader will have complete control over when to transmit a packet and when it can receive a packet of data. network is the reverse collective line protocol co or that described in U.S. Patent No. 5,276,680 assigned to Telesystens S / U Inc., the entire contents thereof are incorporated herein by reference. the reverse collective line protocol network, the portable device radio can transmit data packets to a network access point at any time, subject to the carrier frequency being free. However, the access point can only send a packet to the portable device within a time window that follows receipt of a packet from the portable device. To ensure that the access point has enough units to transmit data to the port, the laptop will periodically send packets even if they do not contain any data. Although the wide-spectrum radio is effective for transmitting the decoded contents of a data array, the limited bandwidth of the radio makes it impractical to transmit a complete uncompressed image. A useful image compression algorithm to reduce the size of a digital image file is the small wave transformation of the dimensions, as described in ñ 64 b / s Vedeo Code Using the 2-D UAVletlet Transforrn by AS. S. Lewis and G. Knowles, published on IEEE Computer Society press, order number 2202. For example, the small-wave HARC transformation system, available from Houston Advance Research Center-in Houston Texas, can be used to compress the photographic image before it is transmitted with an image compression ratio of up to 400: 1. Because the data collection system is designed for portable use, it is to some extent possible that an operator that works In a remote location of the installation, you may need to request supervision instructions while capturing data forms, therefore, the data collection system of this invention includes a data processing board. and voicemail 37 so that the operator can communicate verbally with other people through the broad-spectrum network. Referring to Figure 12, a block diagram of the voice mail circuit is shown, which may be in the form of a microprocessor or voice mail processing board 33 and a terminal control board 31. A voice message is input through an audio input circuit 92 which may include an internal microphone or a port for connection to an external microphone, which will be described later in detail. A digitizer / compression module 94 will create a digital data file representative of the audio input. Before transmitting the message, message control unit 98 will instruct the operator to identify the recipient. The indication may take the form of an audible signal to the operator through the audio output circuit 100 (described below), or display a message on the screen. In a time window that follows the indication, the operator must identify the recipient. This can be done through the keyboard 22 or the touch panel 44 (shown in Figures 8-9). In alternative form, the recipient can be identified by the audio input. In this mode, the speech recognition circuit 102 will operate to convert the audio signal to a digital address. The message control unit 98 will add the address to the message and retransmit the message to the broad spectrum tranceptor for transmission to the recipient. It should be appreciated that the voice mail system may require the identification of the target to be killed by the operator before or after the entry of the message. The message control unit 98 functions to receive data files representative of voice mail messages that enter and store such messages in the memory 96. After receiving an input message, the control unit 90 notifies the operator of the reception through the audio output circuit 100, the screen presentation or a dedicated illuminator. After indicating the operator to issue the voice mail message, the control unit 98 will remove the data file from the memory. A decompression module will convert the data file into a analog signal and an audio output circuit, which can include a speaker or a port for a remote speaker or headphones that will broadcast the message. The indication of the operator to issue the message may be through the keyboard 22, the touch panel 44 or the voice input circuit 92. After the message is output, the voice mail unit of this invention may optionally store the message. the message for later reproduction or to erase the message. With storage or deletion, the message can be advanced or reimposed to it. The control unit will indicate to the operator to enter the vain changes of these options. If the message is stored, the digital data file will remain on the memory 96. If it is advanced, the data file or a copy will be appropriately directed towards the wide radio 33. If the answer option is selected, the identity of the the address of the response message is known and the control unit 98 indicates the operator to enter a response message. The representative digital data file is sent by the transmission radius. Referring to Figure 9, the loudspeaker 50 and microphone 52 are preferably positioned so that the reader can be held along the side of the operator's face as a telephone communication device. Referring to Figure 13, the speaker and the microphone have the shape of wireless headphones. The hearing aids include a headband 115 for holding the device at the operator's head, a loudspeaker 117 positioned close to the operator's ear-and a microphone 119 positioned near the operator's mouth. A microradio module and a power source are located in a housing 121 fixed to the hearing aids. Referring again to FIG. 10, the housing includes a similar microradio formed on the board 35 for transceiving air signals with the headphones. The pucroradio operates in a narrowband modulation scheme in which the band is aligned at a null point of the frequency spectrum of the broad-spectrum radio. In addition to operating in conjunction with wireless headsets, the microradio can function as a wireless peripheral port so that the operator can print a data form label without physically connecting the data collection system to a printer. Printers or other peripheral devices with similar radio dashboards can be placed through the installation in which the data collection system is operated. When an operator approaches the peripheral device with the system, a hand-shake sequence is initiated and an wireless link is established. The data can then be printed on the device p >epfépco Because the data collection system of this invention is designed for portable use, it is desirable that the power source 48 provide a function over an extended period of time without requiring recharging. Although the power source 48 can be any rechargeable cell, the preferable power source is a plurality of flexible lithium polymer battery cells. Each flexible sheet is approximately 2 microns thick and appears to be a plastic sheet. To construct such a cell, Li n2 0¿ is used as the cathode and carbon as the anode. Such a cell is available from Bellcore of Red Bank, New 3ersey. An advantage of the lithium polymer cells is that the shape factor of the flexible sheet is such that the cells can be folded and placed in areas of the housing that have an inadequate space for the traditional cylindrical cells. In Figure 9, the polymer cells 48 are advantageously shown along the surface of the interior of the housing wherein the polymer cells also function to reduce unwanted EMS. In addition to the form factor and the EMS advantages, the lithium polymer cells are rechargeable and provide approximately 3 times the energy density of the NiCad cells and do not undergo the crystallization of the NiCad that produces the degenerative memory effect. Although the description has described the preferred embodiments of the invention, those skilled in the art will recognize that other modifications may be made without departing from the invention and it is desired to claim all modifications and variations that fall within the scope of the invention. The statute, the invention has been described in a more or less specific language in terms of the structural and methodical characteristics, However, it should be understood that the invention is not limited to the specific characteristics shown and described, since the means described in The present invention comprises preferred forms of effecting the invention. n is claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine or equivalents.

Claims (18)

33 NOVELTY OF THE INVENTION CLAIMS

1. - A data form reader module based on an image where two dimensions configured for use in a data form reader, the reader module consists of: a camera assembly that includes an image sensor configured to detect a reflected image from an illuminated region that includes a data form; a lighting module configured to illuminate a data form to be detected by * the camera assembly; control circuits that include a microprocessor to which the camera assembly and the lighting module are operatively coupled; Gain control circuits located in the control circuit and configured to set a gain value to a gain setting used during a previous data form read session, the exposure control circuits located in the control circuit and configured to set a period of exposure to a period stored in the memory used during a previous data form read session; and image processing circuits in code form operable by a nicroprocessor, which is operative to decode the image of detected data form; and further characterized in that the gain value and the set exposure period are each set to recent values at ignition, after which successive fields of image data are captured and the correct gain and exposure are calculated by reducing the latency time. to make correct values.

2. The data form reader according to claim 1, further characterized in that the carnara assembly consists of a board camera having an input port to receive a power signal to turn on the generation of a signal Rnixta video, a gain control port and a gain adjustment circuit connected to the gain control input port configured to bypass analog gain control circuits.

3. The data form reader according to claim 2, further characterized in that it consists of a Ü / A converter, in which the gain control circuit provides a digital value to the D / A converter, which supplies a voltage signal to the gain adjustment circuit in the board deck.

4. The data reader according to claim 2, further characterized in that the gain control circuit consists of a digital gain control circuit formed by a code executed by the microprocessor.

5. The data form reader according to claim 4, further characterized p > orque consists of a observation board that correlates the resulting field of image data to gain values so that a correct gain value can be determined for use in a subsequent image capture.

6. The data form reader according to claim 1, further characterized in that it consists of a dashboard board that includes an input port that provides operating power to generate a mixed video signal,? N input port of exposure control and an exposure time control circuit connected to the exposure control input port configured to bypass the analog exposure control circuitry.

7. The data format reader according to claim 6, further characterized in that it consists of a D / A converter, in which the exposure control circuit provides a digital value to the D / A converter, which supplies signals of voltage to the exposure time control circuit in the dashboard.

8. The data form reader according to claim 7, further characterized in that the circuit (ie, exposure control) consists of a digital exposure control circuit in the form of a code executed by the microprocessor. of data form according to claim 8, further characterized in that it consists of an observation board that correlates the resulting field of the image data to exposure duration values so that a correct exposure duration value can be determined for s? Use in a subsequent image capture. 10. The data form reader according to claim 5, further characterized in that it consists of an exposure control input port and an exposure time control circuit connected to the exposure control input port, and configured to bypass analog exposure control circuits, wherein the exposure control circuit provides a digital value to the D / A converter, which supplies voltage signals to the exposure time control circuit in the board chamber, and the exposure control circuit consists of a digital exposure control circuit in the form of a code executed by the microprocessor and the observation board correlates the resulting field of the image data to exposure duration values so that a value of Correct exposure duration can be determined for use in a subsequent image capture. 11. The data form reader according to claim 3, further characterized in that the gain control circuit is configured to quickly perform a corrected video signal through a minimum latency time. 12. The data format reader according to claim 7, further characterized in that the exposure control circuit is configured to quickly perform a corrected video signal through a latency type. 13. The reader of data form according to claim 1, further characterized p >The control circuit is arranged in a control and decoding board in which the gain control circuit, the exposure control circuit and the image processing circuit are configured in combination with the microprocessor. 14. The data form reader according to claim 12, further characterized in that it consists of a data transfer link configured to create an interface of the control board with a host computer. 15.- A data form reader module based on an image where two dimensions configured for use in a data form reader, the reader module consists of: a camera assembly that includes an image sensor configured to detect? Na reflected image of an illuminated region that includes a data form; a lighting module configured to illuminate a data array to be detected by the camera assembly; a control board that includes a ricroprocessor to which the camera assembly and the lighting module are operatively coupled; Gain control circuits in the control board, the gain control circuit consists of an open loop gain control system configured to set a gain value to a gain setting used during a data form Read session previous in response to the ignition and will adjust the gain value after evaluating the image data to obtain a corrected gain video signal in a short latency period; and operative image processing circuits for decoding the detected data form image 16.- The data format reader (Je according to claim 15, further characterized in that the camera assembly consists of a board feeder q? e has an input port to receive a power signal to turn on the generation of a mixed video signal, a gain control input port and a gain adjustment circuit connected to the configured gain control input port to divert analog gain control circuits 17. The data form reader according to claim 16, further characterized in that it consists of a D / A converter, in which the gain control circuit provides a digital value to the D / A converter, which supplies a voltage signal to the gain adjustment circuit in the dash chamber 18. The data format reader according to claim 16 further characterized in that the gain control circuit consists of a digital gain control circuit in the form of a code executed by the microprocessor. L9.- The data form reader according to claim 18, further characterized in that it consists of an observation board or correlates the resulting field of image data to gain values so that a correct gain value can be determined for use in a subsequent image capture. 20. A data form reader module based on a two-dimensional image configured for use in a data reader, the reader module consists of: an assembly (ie camera that includes an image sensor configured for detecting a reflected image of an illuminated region that includes a data form;? n lighting module configured to illuminate a form of data to be detected by the camera assembly; a circuit control board that includes? microprocessor to which the camera assembly and lighting module are coupled; exposure control circuits located on the control board and configured to establish a period of exposure to a period stored in the memory used during a previous data reading session; operable image processing circuits decode the image of detected data form 21.- EJ data format reader according to claim 20, c further characterized because it consists of a dashboard camera that includes an input port that provides operating power to generate a mixed video signal,? n exposure input port and an exposure time control circuit connected to the input port of exposure set to bypass an analog exposure control circuit. 22. The data form reader according to claim 21, further characterized in that it consists of a D / O converter and an exposure control circuit, in which the exposure control circuit provides a digital value to the D converter / A, which supplies voltage signals to the exposure adjustment circuit in the dash chamber. 23. The data format reader according to claim 22, further characterized in that the exposure control circuit consists of a digital exposure control circuit in the form of a code executed by the microprocessor. 24. The data reader according to claim 23, further characterized in that it consists of an observation board that correlates the resulting image data to gain values so that a correct gain value can be determined for its use. in a subsequent image capture. 25.- A data form reader based on a two-dimensional image configured for use in a data form reader, the reader module consists of: a control circuit board that includes a microprocessor, emulation circuit laser module configured to emulate the output of a laser scanning module coupled with the control circuit board and with an output port, further characterized in that the reader module is constructed and arranged to communicate through the output port with configured devices for use with a laser scanner; further characterized in that the emulation circuit of the laser module provides the electrical capacity with a laser scanning module, while providing the ability to read a variety of data forms including matrix codes. 26. The reader module of data forms according to claim 25, further characterized in that the emulation circuit includes circuits to emulate a square wave video signal and the start of a scrutinizing signal. 27. The data form reader module according to claim 25, further characterized in that it consists of a main control board, in which the control circuit board is a control and decoding circuit board. coupled to the main control board through a data transfer link. 28.- The data form reader module according to claim 25, further characterized in that the laser module emulation circuit is in the form of a code executable by the microprocessor, operable to encode decoded results in a normal size bar code format and output a square wave signal that emulates the square wave signal of a laser scanning module that scrutinizes the code of a dimension. 29.- A data form reader module based on a two-dimensional image for use in a data reader, the reader module consists of; a lighting module that directs illumination towards the target area; and a camera module that includes a photo-sensing device that generates a representative signal of an image of the target area; said camera module has an output interleaving circuit that generates a corrected gain video signal and a reverse input circuit for adjusting said gain in response to a gain control signal. 30.- A data form reader module based on a two-dimensional image for use in a data form reader, the elector module consists of: a module that directs illumination towards a target area; a camera module (g) includes a photo sensor arrangement that generates a signal representative of an image of the target area only in response to an input power signal, and a control circuit configured to provide the input power signal only during a data form reading session and for apgt said power signal at the conclusion of said reading session 31.- The data form reader in accordance with claim 30, further characterized by the conclusion of the session 32.- The reader of data form according to claim 30, further characterized in that the conclusion of the reading session is defined by the expiration of a time window that follows the beginning. of a reading session. SUMMARY OF THE INVENTION An extended work rate data reader with reduced power consumption having a carnage assembly and a circuit control board including gain control circuit and exposure control circuits configured to set a value of initial gain and an initial exposure period, respectively, resulting from a previous data reading session; Subsequent fields of image data are captured by the carnara, which are used p > To correct the gain and exposure relative to the initial values for gain and exposure period, thus reducing the latency period to obtain correct values and reduce the power consumption during power up. In addition, the gain control system and the exposure control system use each open loop real-time feedback so that successive fields of image data captured by the camera are used to capture correct values, thus reducing the latency time for get a correct value. In addition, a reader module is provided for use in a data form reader that emulates a laser module so that the data reader module can be easily integrated into existing data-based reading systems. To be. Preferably, the laser module emulation circuit included in the data form reader module emulates the output of a laser scanning module and a control circuit board, in which the emulation circuit is obtained co o? N exit port built and arranged to communicate with devices configured for use with a scanner- of the ser-. 3NR / aded *? Eoh * casv P97-154F