System for reading barcode symbols

An apparatus for reading indicia having parts of different light reflectivity includes a keyboard for inputting data, a monitor for housing a display, and a reader for reading said indicia, wherein said reader is integrated into either said keyboard or monitor. The apparatus has a particular application in reading barcode symbols in instances where there is a need to save space or where there is a need to avoid the cost of purchasing a separate reader component.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention pertains to the reading of indicia having parts of
 different reflectivity, such as barcode symbols, and more particularly, to
 a reader for reading indicia which is integrated into either a keyboard or
 a monitor. The invention has a particular application in reading barcode
 symbols in instances where there is a need to save space or where there is
 a need to avoid the cost of purchasing a separate reader component.
 2. Description of Related Art
 Various optical readers and scanning systems have been developed for
 reading barcode symbols appearing on a label or the surface of an article.
 The barcode symbol itself can be a coded pattern of indicia comprising a
 series of bars of various widths spaced apart from one another to bound
 spaces of various widths, the bars and spaces having different
 light-reflecting characteristics. The readers and scanning systems
 electro-optically transform the graphic indicia into electrical signals,
 which are decoded into alphanumerical characters intended to be
 descriptive of the article or some characteristic of it. Such characters
 typically are represented in digital form and utilized as an input to a
 data processing system for applications in point-of-sale processing,
 inventory control and other applications. Scanning systems of this general
 type have been disclosed, for example, in U.S. Pat. Nos. 4,251,798;
 4,360,798; 4,369,361; 4,387,297; 4,409,470 and 4,460,120, all assigned to
 the assignee of the present invention and incorporated herein by
 reference.
 One embodiment of such a scanning system, as disclosed in some of the above
 patents, resides in, inter alia, a hand-held, portable laser scanning head
 supported by a user. The scanning head is configured to enable the user to
 aim the head at a target to emit a light beam toward a symbol to be read.
 In another embodiment, the scanning system is a generally bigger and
 separate workstation, which communicates with a data processing unit. For
 example, U.S. Pat. No. 4,369,361 discloses such a system and is assigned
 to the assignee of the present invention and is incorporated herein by
 reference.
 The light source in a laser scanner is typically a gas or semiconductor
 laser. Use of semiconductor devices as the light source in scanning
 systems is particularly desirable because of its small size, low cost and
 low power requirements. The laser beam is optically modified, typically by
 a lens, to form a beam spot of a certain size at the target distance. In
 the one embodiment, the beam spot size at the target distance is
 approximately the same as the minimum width between regions of different
 light reflectivity, i.e., the bars and spaces of the symbol.
 The barcode symbols are formed from bars or elements typically rectangular
 in shape with a variety of possible widths. The specific arrangement of
 elements defines the character represented according to a set of rules and
 definitions specified by the code or "symbology" used. The relative size
 of the bars and spaces is determined by the type of coding used, as is the
 actual size of the bars and spaces. The number of characters per inch
 represented by the barcode symbol is referred to as the density of the
 symbol. To encode a desired sequence of characters, a collection of
 element arrangements is concatenated together to form the complete barcode
 symbol, with each character of the message being represented by its own
 corresponding group of elements. In some symbologies, a unique "start" and
 "stop" character is used to indicate where the barcode begins and ends. A
 number of different barcode symbologies exist. These symbologies include
 UPC/EAN, Code 39, Code 128, Codabar, and Interleaved 2 or 5, among others.
 In order to increase the amount of data that can be represented or stored
 on a given amount of surface area, several new barcode symbologies have
 recently been developed. One example of such a symbology is known as
 two-dimensional (2D) symbology and is discussed in detail in commonly
 assigned U.S. Pat. Nos. 5,243,655 and 5,304,786, which are incorporated
 herein by reference. Briefly, that symbology involves a variable number of
 component symbols of "code words" per row of a nonvolatile electro-optical
 read-only memory imprinted on a substrate. Code words in alternating rows
 are selected from mutually exclusive subsets of a mark pattern, the
 subsets being defined in terms of particular values of discriminator
 function which is illustrated in the referenced patents as being a
 function of the widths of bars and spaces in a given code word.
 In the scanning systems known in the art, the light beam is directed by a
 lens or similar optical components along a light path toward a target that
 includes a barcode symbol on the surface. The scanning systems function by
 repetitively scanning the light beam in a line or series of lines across
 the symbol. The scanning component may either sweep the beam spot across
 the symbol and trace a scan line across the symbol or scan the field of
 view of the scanner, or do both.
 Scanning systems also include a sensor or photodetector, which functions to
 detect light reflected from the symbol. The photodetector is therefore
 positioned in the scanner or in an optical path in which it has a field of
 view, which extends across and slightly past the symbol. A portion of the
 reflected light which is reflected off the symbol is detected and
 converted into an electrical signal. Electronic circuitry or software
 thereafter decodes the electrical signal into a digital representation of
 the data represented by the symbol that has been scanned. For example, the
 analog electrical signal from the photodetector may typically be converted
 into a pulse width modulated digital signal, with the widths corresponding
 to the physical widths of the bars and spaces. Such a signal is then
 decoded according to the specific symbology into a binary representation
 of the data encoded in the symbol, and to the alphanumeric character so
 represented.
 The decoding process in known scanning systems usually works in the
 following way. The decoder receives the pulse width modulated digital
 signal from the scanner, and an algorithm implemented in software attempts
 to decode the scan. If the start and stop characters and the characters
 between them in the scan were decoded successfully and completely, the
 decoding process terminates and an indicator of a successful read such as
 a green light and/or an audible beep is provided to the user. Otherwise,
 the decode receives the next scan, performs another decode attempt of that
 scan, and so on, until a completely decoded scan is achieved or no more
 scans are available.
 Decoding 2D symbology is discussed particularly and shown in various
 flowcharts set forth in the 2D symbology patents incorporated by reference
 and above identified.
 More sophisticated scanning, described in U.S. Pat. No. 5,235,167, assigned
 to the assignee of this invention, and incorporated herein by reference,
 carries out selective scanning of 1-D and 2-D barcodes. Preliminary
 information, such as the barcode type and size, is first decoded during an
 aiming mode of operation when a relatively narrow and visible raster
 pattern is impinged on the target. Based upon the preliminary information
 received by the scanner in the form of light reflected from the target,
 converted to an electrical signal and decoded, an appropriately sized
 raster scan pattern is generated. If the barcode pattern is found to be
 skewed or misaligned with respect to the direction of the raster scanning
 pattern, the pattern is generated with an orientation in alignment with
 the barcode.
 Another type of barcode reader performs an omni-directional scan. For
 example, U.S. Pat. No. 5,481,099, assigned to the assignee of the present
 invention and incorporated herein by reference, shows a scanner for
 reading indicia having portions of differing light reflectivity which has
 a means for directing a light beam from the scanner towards the indicia
 and collecting reflected light returning from the indicia. The scanner
 includes a scanning arrangement with a scanner component, such as a
 mirror. First and second vibratory means support the scanner component for
 angular oscillatory movement to scan the light beam in first and second
 orthogonal scan directions. The scanning arrangement includes read-start
 means for moving the scanner component to simultaneously scan the light
 beam in the first and second scan directions. Control means, operatively
 connected to the read-start means, are provided for imparting differing
 signals to the read-start means to (1) alternatively drive fast and slow
 vibrations of the first and second vibratory means to vary the scanning of
 the light beam in the first scan direction and (2) to drive vibration of
 only the second vibratory means to cause the scanning of the light beam in
 the second scan direction. The scanning of the light beam in the first and
 second scan directions generates a scan pattern over the indicia.
 Another type of barcode reader is one which incorporates an imaging sensor,
 such as a charge coupled device or other solid state imaging device.
 Examples of such a reader are shown in U.S. Pat. Nos. 5,672,858 and
 5,591,952, assigned to the assignee of the present invention and
 incorporated herein by reference.
 CCDs consist of an array of many detectors, commonly referred to as
 "pixels." The entire symbol is flooded with light from the reader or
 ambient light, and each pixel is sequentially read out to determine the
 presence of a bar or a space. Such readers are light-weight and easy to
 use, but require substantially direct contact or placement of the reader
 on the symbol to enable the symbol to be properly read. Such a physical
 contact of the reader with the symbol is preferred mode of operation for
 many applications, or as a matter of personal preference by the user.
 A basic figure of merit in scanning CCD arrays is a so-called "pixels per
 module" detection. If detection capability fall below such a figure of
 merit, scanning cannot proceed since requisite sensitivity is not present.
 As noted above briefly, one type of a scanning system is a separate
 scanning workstation that communicates with a data processing unit. As
 shown in U.S. Pat. No. 4,369,361, the workstation can take up a
 significant amount of working space. Also, the workstation can take up an
 additional port space on the data processing unit. Of course, there are
 situations where space is at a premium or cannot be spared. In such
 situations, an additional scanning workstation can cause great
 inconvenience or cannot be used. Additionally, the workstation can
 necessitate additional costs: purchasing and maintenance costs, for
 example. There is a need for an improved scanning system that overcomes
 the above noted shortcomings.
 SUMMARY OF THE INVENTION
 The present invention provides an improved apparatus for reading indicia
 having parts of different light reflectivity comprising a reader
 integrated into a keyboard or a monitor, so that savings are achieved in
 space and cost over having a separate reader component.
 In one embodiment, an apparatus for reading indicia having parts of
 different light reflectivity, comprises a keyboard for inputting data; and
 a reader for reading the indicia, wherein the reader is integrated into
 the keyboard.
 The reader may comprise a laser scanner or an imaging device for imaging
 the indicia. Additionally, the reader may comprise a CCD imaging device
 for imaging the indicia. The reader may comprise a light emitting means
 for two-directionally or omni-directionally scanning the indicia.
 The reader may be integrated at various positions. For example, the reader
 may be integrated at a right top portion of the keyboard, a left top
 portion of the keyboard, a right side portion of the keyboard, a left side
 portion of the keyboard. Also, the reader may comprise a light emitting
 means for emitting light directed at a variable angle from a planar
 surface of the keyboard.
 Also, the keyboard may obtain power and transmit data through a cable
 connected to a data processing unit, the reader may be integrated into the
 keyboard, and the reader may obtain power and transmit data through the
 cable. Alternatively, the reader may transmit data by sending radio
 frequency signals. Also, the reader may be adjustably oriented at
 different angles from a planar surface of the keyboard.
 In another embodiment, an apparatus for reading indicia having parts of
 different light reflectivity comprises a monitor for housing a display;
 and a reader for reading the indicia, wherein the reader is integrated
 into the monitor.
 Similar to the above embodiment, the reader may comprise a laser scanner or
 an imaging device for imaging the indicia. The reader may comprise a light
 emitting means for emitting light directed at a variable angle from a
 planar surface of the monitor. Also, the reader may be adjustably oriented
 at different angles from a planar surface of the monitor.
 In another embodiment, an apparatus for reading indicia having parts of
 different light reflectivity comprises a keyboard for inputting data; and
 a reader for reading the indicia, wherein the reader is integrated into
 the keyboard, and the reader comprises a light emitter for emitting light
 through a surface of either the keyboard; an optical scanning means for
 automatically causing the light from the emitter to scan across the
 indicia; a photodetector for sensing light reflected from the indicia and
 producing an electrical signal representative of the indicia; and a signal
 processing means for analyzing the indicia represented by the electrical
 signal and providing a decoded information representative of the indicia.
 Again, the reader may comprise a light emitting means for two-directionally
 or omni-directionally scanning the indicia. Also, the reader may be
 positioned at different locations. For example, the reader may be
 integrated into a right top portion of the keyboard, a left top portion of
 the keyboard, a right side portion of the keyboard, or a left side portion
 of the keyboard.
 Furthermore, the reader may comprise a light emitting means for emitting
 light directed at a variable angle from a planar surface of the keyboard.
 Also, the keyboard may obtain power and transmit data through a cable
 connected to a data processing unit, the reader is integrated into the
 keyboard, and the reader may obtain power and transmit data through the
 cable. Alternatively, the reader may transmit data by sending radio
 frequency signals. Also, the reader may be adjustably oriented at
 different angles from a planar surface of the keyboard.
 In another embodiment, an apparatus for reading indicia having parts of
 different light reflectivity comprises a monitor for housing a display;
 and a reader for reading the indicia, wherein the reader is integrated
 into the monitor, and the reader comprises a light emitter for emitting
 light through a surface of either the monitor; an optical scanning means
 for automatically causing the light from the emitter to scan across the
 indicia; a photodetector for sensing light reflected from the indicia and
 producing an electrical signal representative of the indicia; and a signal
 processing means for analyzing the indicia represented by the electrical
 signal and providing a decoded information representative of the indicia.
 The reader may comprise a light emitting means for emitting light directed
 at a variable angle from a planar surface of the monitor. Also, the reader
 may be adjustably oriented at different angles from a planar surface of
 the monitor.
 In another embodiment, an apparatus for reading indicia having parts of
 different light reflectivity comprises a keyboard; and a reading means for
 reading the indicia, wherein the reading means is integrated into the
 keyboard, and the reading means comprises a light emitter for emitting
 light to illuminate sequential portions of the indicia through a surface
 of the keyboard; an array of solid state imaging devices for detecting
 light reflected from portions of the indicia by scanning a field of view
 and for generating an electrical signal representative of the portions of
 the indicia; and a signal processor for analyzing the indicia represented
 by the electrical signal and providing a decoded information
 representative of the indicia.
 The reader may comprise a CCD imaging device for imaging the indicia. Also,
 the reader may comprise a light emitting means for two-directionally or
 omni-directionally scanning the indicia.
 The reader may be positioned at different locations. For example, the
 reader may be integrated into a right top portion of the keyboard, a left
 top portion of the keyboard, a right side portion of the keyboard, or a
 left side portion of the keyboard. The reader may comprise a light
 emitting means for emitting light directed at a variable angle from a
 planar surface of the keyboard. Also, the keyboard may obtain power and
 transmit data through a cable connected to a data processing unit, the
 reader is integrated into the keyboard, and the reader may obtain power
 and transmit data through the cable. The reader may also transmit data by
 sending radio frequency signals. Also, the reader may be adjustably
 oriented at different angles from a planar surface of the keyboard.
 In another embodiment, an apparatus for reading indicia having parts of
 different light reflectivity comprises a monitor for housing a display;
 and a reader for reading the indicia, wherein the reader is integrated
 into the monitor, and the reading means comprises a light emitter for
 emitting light to illuminate sequential portions of the indicia through a
 surface of the monitor; an array of solid state imaging devices for
 detecting light reflected from portions of the indicia by scanning a field
 of view and for generating an electrical signal representative of the
 portions of the indicia; and a signal processor for analyzing the indicia
 represented by the electrical signal and providing a decoded information
 representative of the indicia.
 The reader may comprise a light emitting means for emitting light directed
 at a variable angle from a planar surface of the monitor. Also, the reader
 may be adjustably oriented at different angles from a planar surface of
 the monitor.
 In another embodiment, an apparatus for reading indicia having parts of
 different light reflectivity comprises a point-of-sale unit; and a reader
 for reading the indicia, wherein the reader is integrated into the
 point-of-sale unit.
 The reader may comprise a laser scanner or an imaging device for imaging
 the indicia. Also, the reader may comprise a light emitting means for
 emitting light directed at a variable angle from a planar surface of the
 point-of-sale unit. Also, the reader may be adjustably oriented at
 different angles from a planar surface of the point-of-sale unit.
 The above and other advantages, features and aspects of the present
 invention will be more readily perceived from the following description of
 the preferred embodiments thereof taken together with the accompanying
 drawings and claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 With reference to FIG. 1, a first embodiment of the present invention is
 indicated generally by the reference numeral 10. Reader 20 for reading
 barcode symbols is integrated into keyboard 200 and reader 30 is
 integrated into monitor 300. The keyboard, in one embodiment, may be a
 standard computer keyboard with a full set of alphanumeric characters. Of
 course, just one reader may be used as needed (e.g., just reader 20 being
 used with a monitor that does not have a reader). This arrangement
 according to the present invention saves space and cost in obviating a
 dedicated reader module 600, an associated cable 601, and port space on a
 data processing system 602, which as shown in FIG. 2, take up additional
 space. For brevity sake, the associated electronics in the keyboard and
 the monitor are not shown and may include relatively standard electronics.
 The monitor could be a CRT monitor, a touch-screen monitor, an LCD
 monitor, or another type of monitor.
 In operation, for example, a user 500 can cause the barcode symbol 401 on
 an object 400 to move over either reader 20 or reader 30. The object 400
 could be any object with a barcode symbol, but could, for example, be an
 ID card used at motor vehicle centers. The reader may be a laser scanner
 and/or an imaging device (which, for example, could be a CCD imaging
 device).
 More specifically, as an example, FIG. 3 shows reader 90 integrated into
 either a monitor or a keyboard 900. The reader 90 may be enclosed in
 housing 99, which may be integral to monitor/keyboard 900. Alternatively,
 the housing may be attached to the monitor/keyboard 900 by adhesive,
 screws, or other fastening means. In FIG. 3, the housing 99 contains a
 semiconductor laser light source 92, photodetector 100, optics 101, 93,
 and 94 and signal processing/control circuitry 96.
 In operation, a suitable lens or a multiple lens system, will focus the
 scanned beam onto the barcode symbol 401 at an appropriate reference frame
 through window 91. The semiconductor light source 92 is positioned to
 introduce a light beam into the axis of the lens 101, and the beam passes
 through a partially silvered mirror 93 and other lenses or beam shaping
 structure, as needed. An oscillating mirror 94 is connected to a scanning
 motor 95 that is driven by the signal processing/control circuitry 96.
 Signals to and from the signal processing/control circuitry 96 are carried
 by exit port 97 and line 98 to a data processing unit, either directly or
 via the keyboard or monitor circuitry. Line 98 may also supply power to
 the reader 90, although it is also possible to have an internal power
 source, such as a battery, within the housing 99.
 Additionally, the reader according to the present invention may employ
 imaging technology, which may be useful for certain applications. As
 exemplified in FIG. 4, reader 150 is integrated into either a monitor or a
 keyboard 900, as in FIG. 3. The reader 150 may be enclosed in a housing
 (not shown) similar to the one shown in FIG. 3 and light is transmitted
 and received via window 155, which is similar to window 91 in FIG. 3.
 The reader 150 optically images or focuses a barcode symbol 401, which is
 part of a field of view 402, onto a photodetector array 151 as 401', using
 a suitable optical system represented by a lens 152. A light source 153,
 for example, of the light-emitting diode type, or an incandescent or
 florescent lamp, or the like, illuminates the field of view 402 through a
 suitable lens system 154, although ambient light could be used to
 illuminate the field instead.
 It is common to use red LEDs as the light source 153 and red filters in the
 optics to filter out unwanted light, thus increasing the signal-to-noise
 ratio. The photodetector array 151 is in one embodiment a charge coupled
 device (CCD) of the type commercially available, although other types of
 photodetector arrays are also suitable, such as a charge injection device
 (CID).
 Instead of a CCD, for example, a light-responsive memory device can be used
 to both convert the image to a binary representation of incident light,
 and to store the binary data for access by a CPU for code recognition: one
 such memory device is an OpticRAM.TM. device commercially available from
 Micron Technology, Inc., Boise, Id. This OpticRAM.TM. device is a 64K or
 256K dynamic RAM array having a light-transparent window above the chip in
 the I/C package, as described in U.S. Pat. No. 4,441,125. Various optical
 systems are known which enhance the function of imaging the field of view
 402 onto the photodetector array 151, such as automatic focusing
 mechanisms of the type used in commercially available video and 35-mm
 cameras. It is understood that such equipment is useful in the practice of
 this invention. A zoom mechanism may be used to adjust the size of the
 image of the symbol 401 on the photodetector array 151.
 Instead of a semiconductor device such as the CCD or RAM as discussed, the
 photodetector array 151 may be a vidicon of the type used for generating
 TV signals. Standard NTST video employs a vertical resolution of 525 lines
 in an interlaced raster scan, with a horizontal resolution usually about
 400 pixels per line or less, depending upon the quality of the vidicon. As
 discussed below in regard to CCDs, the resolution needed for recognizing
 barcode symbols depends upon the type of barcode, the optics employed,
 size of field of view, average depth of field needed, and etc.
 As illustrated in FIG. 5, the photodetector array 151 of FIG. 4 is used to
 generate an electrical image of the field of view 402 for transferring to
 a semiconductor memory device 170. The array 151 may be a CCD imaging
 device of the type used in hand-held video cameras of the consumer type,
 or the like.
 A CCD device is a silicon chip made by integrated circuit manufacturing
 techniques and functions to create a serial output on a line 171
 representing the light impinging upon each photo-responsive element or
 "picture element" (pixel) in the array. An enlarged view of a small part
 of the array in the CCD device 151 is shown in FIG. 6. A large number of
 photo-elements 180 are arranged in M rows and N columns in this array,
 where M and N are numbers representing the numbers of rows and columns. A
 control input 181 controls the light capture function, and a signal on
 input 181 causes each element to capture and store a charge responsive to
 the light then incident upon this element. The array is then no longer
 sensitive to light after this control input 181 is activated, and the
 charge packets stored in each element can be read out. To this end, the
 rows are shifted into an N-bit shift register 182, one column of elements
 at a time, by clock voltages applied to the elements 180 by lines 183. The
 shift register 182 is clocked out onto the line 184 by clock voltage input
 185. The clock on line 183 can be derived from the clock on input 185 by
 dividing by N, the number of columns in the detector array 151.
 The M.times.N array 151 may be 256.times.256, for example, meaning there
 are 256 rows of elements and 256 elements 180 in each row (256 columns).
 In this case, the clock 185 would occur 256 times for each one of the
 clocks on line 183. The density of the array 151 is selected according to
 the resolution required for the system, and may be less than
 256.times.256, or more. However, continuing with this example, note that
 the memory 170 may also be a 256.times.256 array, in which case a
 one-for-one correspondence is provided between the elements of the array
 151 and the memory cells of the memory device 170. For example, a 64K-bit
 video DRAM of the type commercially available under the part number
 TMS4161 provides a 256.times.256 cell array having both serial and
 random-access I/O ports. This video DRAM device is one example of a device
 suited for use as the memory device 170 because serial access can be at a
 much higher clock rate than the cycle time for random access and because
 random access can be occurring at the same time as serial loading of the
 memory from the CDD occurs.
 If higher resolution is needed, 256K video DRAMs are available providing
 512.times.512 pixel arrays (higher resolution than commercial TV, for
 example), or 1-Mbit video DRAMs providing 1024.times.1024 arrays. For high
 density symbols (using the maximum density of Code-49, for example), a
 2048.times.2048 memory 170 paired with a 2048.times.2048 CCD might be
 optimum. The 2048.times.2048 bit video DRAM could be comprised of four
 1-Mbit video DRAMS, since 4-Mbit video DRAMs are not available at this
 time. Also, other types of memory devices may be employed instead of video
 DRAMs. For example, standard DRAMs having "by 4" I/O data lines may be
 used, or static RAMs with 4-bit or 8-bit wide data I/O paths. Static RAMs
 provide faster access than DRAMs, but use more power and are more
 expensive.
 In the circuit of FIGS. 5 and 6, the clock input 185 used to shift the bits
 out of the N-bit shift register 182 of the CCD device 151 is also used as
 a serial clock input 185 to the video DRAM, since the data will be clocked
 out of the CCD 151 in synchronization with clocking-in of the serial data
 bits at serial input 186 to the DRAM 170. Likewise, the same clock 183
 used to shift the columns of charge packets into the shift register 182 of
 the CCD can be used to transfer the N bits of incoming data from a shift
 register 187 in the input of the video DRAM 10 to column lines 188 in the
 cell array. The DRAM 170 has an array of dynamic memory cells 189 in rows
 and columns having a one-for-one correspondence to the photo-responsive
 elements 180, so there are M rows and N columns of cells. So after N clock
 pulses (256, in the example) on the input 185, the shift register 187 is
 full, and one clock on input 183 loads this N-bits of data onto the N
 column lines 188. Then, one or the N row lines 190 is activated by a row
 decoder to load this N-bits of data to one of the rows of memory cells
 188, where they will remain stored until written over.
 The sequence then repeats. Another N bits are shifted into shift register
 182 of the CCD, then clocked out by clock 185 while being clocked into the
 shift register 187 of the DRAM 170. So, after M.times.N clocks on line
 183, or N clocks on line 185, all M.times.N (64K-bits, i.e., 65,536 bits,
 in the example) of data form the photodetector 151 will have been
 transferred to the DRAM 170. The detected light at picture elements 180 of
 the photodetector device 151 is thus transformed into electrical charge
 packets which are transferred in a bit-mapped manner into the memory 170
 one-for-one, in corresponding locations. A threshold-responsive buffer 192
 is used between the output 184 of the CCD and the DRAM input 186 if the
 output 184 is analog instead of digital, so that the input 186 is either a
 binary one or a zero, not a variable-level voltage.
 The bit-mapped image in the memory 170 is accessed by a CPU device 172 of
 FIG. 5, where this CPU may be an 8-bit or 16-bit micro controller or
 microprocessor such as part numbers 8042 or 8051 (microcontroller devices)
 or 8086/8088 (microprocessor devices) manufactured by Intel Corporation of
 Santa Clara, Calif. The microprocessor type selected depends upon the
 level of performance needed for the particular system. The 8051 type of
 microcontroller has an internal (on-chip) ROM or EPROM for program
 storage, and an internal RAM for temporary data storage, while an 8086
 type of microprocessor requires an external memory 173 for storing
 programs and data. If an external read/write memory 173 is included, the
 image data from memory 170 can be loaded into this memory 173 for further
 processing, such as employing graphics algorithms of the translate/rotate
 type. For example, if the memory 170 is used as the principle storage
 location for the image data, however, then rewriting transposed image data
 to this memory 170 by the CPU 172 will destroy existing image data,
 allowing limited transposition. A system bus 174 includes an address bus
 174a, a data bus 174b and a control bus 174c. The bus is used for
 accessing the memory 173 if one is needed, and of course, for accessing
 the video DRAM 170, as well as for accessing an I/O controller (or
 controllers) 175 for communicating with a keyboard input, a display, or
 data output to a host computer, or the like.
 The video DRAM 170 is a dual-ported memory; in addition to the serial port
 186 described above, the video DRAM 20 has "random access" type of data
 I/O port 193 connected to the data bus 174b for accessing the bit-mapped
 image data by the CPU. The video DRAM can have a 4-bit wide data I/O port
 193, so four bits are accessed in parallel at one time, instead of 1-bit.
 The video DRAM has a multiplexed address input on lines 194 connected to
 address bus 174a. A row address is applied first, along with a row address
 strobe on the control bus 174c. Then, a column address is applied along
 with a column address strobe. These addresses are loaded into address
 buffers for the row and column decoders 191 and 195. Thus, for a 64K video
 DRAM, an 8-bit address is applied to the decoder 191 from the CPU to make
 a 1-of-256 selection for loading the serial register 187 to one of the
 rows of the cells 189. This loading also requires the sense amplifiers to
 be strobed, which occurs when the row address strobe is activated. If an
 8-bit address is applied to the decoder 191 to select a row for input to
 the column decoder 195 from the CPU to select a column or columns for
 output on the data I/O bus 193 via the data bus 174b to the CPU 172. In
 this manner, the CPU accesses the bit-mapped image data in the memory 170
 to thereby scan and interpret the image of the field of view 402, find the
 symbol 401, and decode the characters in the symbol. The above discussion
 provides and example of an imaging device using CCD technology. Of course,
 other types of imaging devices may be used (e.g., as noted above, a CID, a
 vidicon, and others).
 Turning back to FIG. 1, keyboard 200 may obtain power and transmit data
 through cable 201 connected to a data processing unit 800. The reader 20
 may then obtain power and transmits data through cable 201. Similarly,
 monitor 300 may obtain power and transmit data through cable 301 connected
 to a data processing unit 800. The reader 30 may then obtain power and
 transmits data through cable 301. Alternatively, readers 20 and 30 may
 transmit data by sending radio frequency signals to a data processing
 unit, either to data processing unit 800 or to another data processing
 unit.
 Furthermore, the reader 20 or 30 may be a light emitting means for one,
 two, and/or omni-directionally scanning the indicia, using means disclosed
 in the related patents discussed above.
 In one embodiment, the reader 20 is integrated into a right top portion of
 keyboard 200, as shown in FIG. 1. This facilitates the ease with which a
 user may scan a barcode. The user 500 may move the article 401 in a
 right-to-left direction over reader 20. Alternatively, the reader 20 may
 be integrated into the left top portion of keyboard 200, as shown in FIG.
 7. This positioning may be easier for left-handed users. Additionally, a
 reader 40 may be integrated into the right side portion of keyboard 200 or
 a reader 60 may be integrated into the left side portion of keyboard 200.
 Alternatively, the user 500 can scan barcode 401 with the reader 30, which
 is integrated into a right top portion of monitor 300. User 500 would move
 article 401 in a direction lying over a plane which is parallel to the
 side of the monitor 300 facing the user. Again, the reader 30 may
 alternatively be placed on the left top portion of monitor 300, as shown
 in FIG. 7, which may be easier to use for left-handed persons.
 Furthermore, the reader 50 may be placed on the right side portion of
 monitor 300, as shown in FIG. 7, or the reader 55 may be placed on the
 left side portion of monitor 300, as shown in FIG. 8.
 Of course, the above described positions of the reader are only exemplary
 and the present invention encompasses other positions, as needed for
 different needs and applications.
 In another embodiment shown in FIG. 8, reader 30 is angled down at 45
 degrees from a planar surface of monitor 300. This position makes it easy
 for user 500 to scan a barcode symbol 401 on article 400 because the
 user=s arm generally approaches the monitor not at a 90 degrees angle with
 respect to the front planar surface of the monitor, but closer to a 45
 degrees angle. Of course, the reader 30 may emit light directed down at a
 variable angle from the planar surface of the monitor 300, as needed
 (e.g., 30 degrees instead of 45 degrees). This would apply to reader 20,
 as well, and may be achieved either by the proper placement of the housing
 at an appropriate angle (e.g., housing 99 in FIG. 3), the placement or the
 parts controlling the direction of the light beam (e.g., optics 101, 93
 and 94), and/or other means known in the art.
 In another embodiment, as exemplified in FIG. 9, the angle of scan can be
 adjusted by the user by adjusting the reader 20 as desired. For example,
 the light beam can be made to come out at the center of the
 semi-spherically shaped reader 20 at a location 250. The reader 20 is
 constructed so that it can move in any direction above a planar surface of
 keyboard 200 (or monitor 300) as needed in a particular situation. For
 example, the user may rotate the reader 20 to a direction 251, to the
 right of the keyboard, for one situation and then later change to a
 direction 252 for a different situation.
 The present invention may also be integrated into a point-of-sale unit, as
 shown in FIG. 10. Reader 70 is integrated into a right top position on the
 point-of-sale unit 700 (of course, the position may be varied as needed).
 User 500 may then scan article 400 by moving barcode symbol 401 (on object
 400) over reader 70. A point-of-sale unit may include, for example, a cash
 register, a lottery ticket dispensing apparatus, or the like. Furthermore,
 as described above, this embodiment may use a laser scanner or an imaging
 device; may employ a light emitting means for two-directionally or
 omni-directionally scanning indicia; may be positioned variably into the
 point-of-sale unit; and may be angled variably.
 Furthermore, in all of the embodiments contemplated in this application, an
 RFID ("Radio Frequency Identification") reader can be used instead of a
 laser scanner or an imaging device, to read RFID tags. RFID systems have
 been disclosed, for example, in U.S. Pat. Nos. 5,768,140, 5,594,228 and
 5,814,799, all assigned to the assignee of the present invention and
 incorporated herein by reference.
 While the present invention has been shown and described with reference to
 preferred embodiments presently contemplated as best modes for carrying
 out the invention, it is understood that various changes may be made in
 adapting the invention to different embodiments without departing from the
 broader inventive concepts disclosed herein and comprehended by the claims
 which follow.