Combination mouse and scanner for reading optically encoded indicia

An optical scanner for reading optically encoded indicia such as a bar code is contained within the same housing as a mouse-type position sensing device. The position sensing portion comprises a track ball extending through a lower opening in the housing and associated movement detection electronics. As the housing is moved by the user across a flat surface, the track ball engages the surface and the associated electronics detect the extent of the movement of the device across the surface. Conveniently located keys allow the user to activate a switch by clicking, and this data along with positional data detected by the track ball electronics is provided as input to an associated computer. The device comprises an optical scanner in the form of a laser beam source, means for oscillating the laser beam so as to produce a scanning beam directed outwardly through a window, and a photodetector for sensing light reflected from a target indicia such as a bar code. The device also comprises a digitizing means for converting the analog signal from the photosensor indicative of the reflectivity of the target indicia into a digital data signal representative thereof. The digital bar pattern is provided to the associated computer along the same transmission means as the positional data.

TECHNICAL FIELD 
The instant invention relates to devices for reading optically encoded 
information, for example bar codes, and to associated data input devices. 
BACKGROUND ART 
Optically encoded information, such as bar codes, have become quite common. 
A bar code symbol consists of a series of light and dark regions, 
typically in the form of rectangles. The widths of the dark regions, the 
bars, and/or the widths of the light spaces between the bars indicates the 
encoded information. A specified number and arrangement of these elements 
represents a character. Standardized encoding schemes specify the 
arrangements for each character, the acceptable widths and spacings of the 
elements the number of characters a symbol may contain or whether symbol 
length is variable, etc. 
To decode a bar code symbol and extract a legitimate message, a bar code 
reader scans the symbol to produce an analog electrical signal 
representative of the scanned symbol. A variety of scanning devices are 
known. The scanner could be a wand type reader including an emitter and a 
detector fixedly mounted in the wand, in which case the user manually 
moves the wand across the symbol. As the wand passes over the bar code, 
the emitter and associated optics produce a light spot which impacts on 
the code, and the detector senses the light reflected back from the light 
spot passing over each symbol of the code. Alternatively, an optical 
moving spot scanner scans a light beam, such as a laser beam, across the 
symbol; and a detector senses reflected light from the beam spot scanned 
across the symbol. In each case, the detector produces the analog scan 
signal representing the encoded information. 
A digitizer processes the analog signal to produce a pulse signal where the 
widths and spacings between the pulses correspond to the widths of the 
bars and the spacings between the bars. The pulse signal from the 
digitizer is applied to a decoder which first determines the pulse widths 
and spacings of the signal from the digitizer. The decoder then analyzes 
the widths and spacings to find and decode a legitimate bar code message. 
This includes analysis to recognize legitimate characters and sequences, 
as defined by the appropriate code standard. 
Problems arise from association of the optical reader with other devices 
connected to a common computer system. In actual use, the device for 
reading optically encoded information typically connects to some form of 
computer. Often a need exists for entry of other data, in addition to that 
scanned by the optical reader. For example, in an inventory system using 
bar code readers the operator scans an item and then enters the quantity 
of such items presently in stock. Consequently, in most systems using 
optical readers of the type discussed above, the system will include 
additional data entry devices coupled to the same computer. Separate data 
entry devices, however, are often inconvenient to carry along in 
conjunction with a portable optical reading device. Also, the use of 
multiple data input devices requires use of several of the option card 
slots of the computer and additional physical wiring connections. 
Furthermore, multiple input devices often create software problems 
directing the multiple data input streams to a single application program 
running on the computer. 
A number of other types of data entry devices are known, and in many 
applications provide more convenient or "user friendly" data entry 
operation than do keyboards and alphanumeric displays. For example, a 
mouse allows a computer operator to move a cursor to point at an option 
illustrated on a display screen. The operator then "clicks" a button on 
the mouse to select the particular option. The mouse can also provide 
graphics data input. U.S. Pat. No. 4,906,843 to Jones et al. discloses a 
combination mouse and optical scanner, but the optical scanner scans 
characters or graphics data, not optically encoded information such as bar 
codes. The user manually scans characters by moving the mouse across the 
surface on which the characters appear. 
From the above discussion it should be clear that a need still exists to 
further develop various computer input devices integrated with means to 
scan optically encoded indicia which also provide convenient operation. 
DISCLOSURE OF THE INVENTION 
It is an objective to incorporate a bar code reader, for example, a moving 
spot scanner, into a mouse type computer data entry device. 
SUMMARY 
The present invention incorporates an optical scanner, for reading 
optically encoded indicia, into a mouse type data input device. This 
embodiment would include a mouse with relatively standard electronics. The 
housing of the mouse also contains a moving spot optical scanner module 
and associated photodetector. The scanner emits a beam of light from the 
bottom surface of the mouse housing, and the photodetector detects the 
variable intensity of the returning portion of the light reflected from 
any object scanned. The photodetector generates an electrical analog 
signal indicative of the detected variable light intensity. Typically, at 
least the digitizer for converting analog signals from the photodetector 
to a pulse signal would also be located within the housing of the mouse. 
In a first version, a user picks up the mouse and activates a third 
trigger switch on the top surface of the housing to activate the optical 
reader. A second version includes a contact switch mounted in the lower 
surface of the housing. The contact switch detects when the mouse is 
resting on a surface and controls the device to provide standard mouse 
type signals to the associated computer. When the operator lifts the mouse 
off the surface, however, the contact switch triggers operation of the 
optical reader. 
Typically, the light beam emitted by the scanners of the present invention 
will be in the visible range of the spectrum, for example red light. 
Consequently, the beam scan across the code or indicia will be visible to 
the operator. Also, the decode logic can provide a "beep" signal as an 
audible output upon detection of a valid read result. The visible beam and 
the "beep" signal provide feedback to the operator as to the operation of 
the scanner. 
Additional objects, advantages and novel features of the invention will be 
set forth in part in the description which follows, and in part will 
become apparent to those skilled in the art upon examination of the 
following or may be learned by practice of the invention. The objects and 
advantages of the invention may be realized and attained by means of the 
instrumentalities and combinations particularly pointed out in the 
appended claims.

BEST MODE FOR CARRYING OUT THE INVENTION 
The present invention incorporates the optical scanner, for reading 
optically encoded indicia, into a mouse type data input device. This 
embodiment would include a mouse with relatively standard electronics. 
FIG. 1A, for example, shows a track ball 43 and associated movement 
detection electronics 45. The housing of the mouse also contains a moving 
spot optical scanner module and associated photodetector. 
The housing is adapted for grasping, typically in the palm of a user's 
hand, for manual movement across a flat surface. When located on the flat 
surface, the track ball extends through an opening in the bottom surface 
of the housing. During movement of the mouse across the surface, the track 
ball 43 engages the surface, and the associated electronics 45 detect the 
extent of the manual movement of the device across the surface. One or two 
keys are located in the top of the housing (see FIG. 1B). Manual 
depression of these keys operates switches (not shown) within the mouse 
housing to provide an operator input. These elements of the embodiment of 
FIGS. 1A and 1B provide standard "mouse" type inputs to an associated 
computer. 
The mouse arrangement of FIG. 1A comprises a housing containing a 
lightweight, high-speed, miniature scanning motor 20 similar to that 
described in U.S. Pat. No. 4,496,831. The motor 20 repetitively drives an 
output shaft 22 in alternate circumferential directions about an axis 
along which the shaft extends over arc lengths less than 360.degree. in 
each direction. U-shaped structure 26 supports a laser emitter and optics 
assembly 28. As the motor 20 repetitively drives output shaft 22 in 
alternate circumferential directions, the subassembly 28 and the support 
structure 26 jointly oscillate and turn with the shaft 22. The subassembly 
28 includes an elongated hollow tube 30, a laser diode 32 fixedly mounted 
at one axial end region of the tube 30, a lens barrel 34 mounted at the 
opposite axial end region of the tube 30. The lens barrel contains a 
focusing lens (not shown) such as a plano-convex lens, but may be 
spherical, convex or cylindrical. 
The solid state laser diode 32, of the subassembly 28, generates an 
incident laser beam, either in the invisible or visible light range. The 
lens focuses the laser beam which is reflected off of a mirror 49, and the 
focused beam passes through the window 40. In this embodiment, the window 
40 is formed in the bottom surface of the mouse housing such that the beam 
cross-section or beam spot will have a certain waist size at distances 
within a working range relative to the housing. Instead of using the 
mirror 49, the motor, support and emitter and optics assembly could be 
positioned to emit light downward through window 40 directly. In either 
case, during the alternate, repetitive oscillations of the shaft 22, as 
the support 26 and the subassembly 28 concurrently oscillate, the beam 
spot sweeps through an arc across the encoded information or bar code 
symbol positioned a distance below the lower surface of the mouse housing. 
The scanner emits a beam of light from the bottom surface of the mouse 
housing, and the photodetector 44 detects the variable intensity of the 
returning portion of the reflected light and generates an electrical 
analog signal indicative of the detected variable light intensity. 
Typically, at least the digitizer for converting analog signals from the 
photodetector to a pulse signal would also be located within the housing 
of the mouse. 
The embodiment of FIGS. 1A and 1B includes a third trigger on the mouse to 
activate the optical reader components (see plan view of FIG. 1B). 
Typically, the user picks up the mouse, orients it so as to direct the 
beam along a path toward the information to be scanned, and activates the 
third trigger switch 42 on the top surface of the housing to activate the 
moving spot scanner and associated photodetector. When the user has not 
activated switch 42, the unit operates as a standard computer mouse. 
A second version of the mouse includes a contact switch 42' mounted in the 
lower surface of the housing, as shown in FIG. 2. The mouse includes the 
components of an optical reader engine or module 70 similar to the 
components 20, 26 and 28 discussed above and includes a standard track 
ball and position detection electronics similar to 43 and 45. The contact 
switch detects when the mouse is resting on a surface and controls the 
device to provide standard mouse type signals to the associated computer. 
When the operator lifts the mouse off the surface, however, the contact 
switch triggers operation of the optical reader module 70. The operator 
then points the mouse so that the beam scans across the optically encoded 
indicia. 
In the mouse embodiments illustrated in the drawings, the mouse connects to 
the associated computer via a cable (FIGS. 1B and 2). This cable could 
connect to a port on the back of the computer or to a port on the 
keyboard. The cable supplies all necessary power to the movement detection 
electronics 45 and any circuitry needed to detect button operation, and it 
supplies all necessary power to the laser diode 32 and motor 20 of the 
scanner, the photodetector 44 and the associated electronics for 
processing the signal from the photodetector. As an alternative, the mouse 
could incorporate a battery and a wireless transmitter. The transmitter 
would send analog or digital signals resulting from the scan of the 
optically encoded information to the associated computer system and the 
signals relating to the mouse movement and button operation. The battery 
would supply all power to the mouse for operation of both the mouse type 
electronics and the optical scanning, detection and signal processing 
electronics for optical reading of indicia. 
Typically, the light beam emitted by the scanners of the present invention 
will be in the visible range of the spectrum, for example red light. 
Consequently, the beam scan across the code or indicia will be visible to 
the operator. The decode logic may reside within the same housing as the 
scanner, or the decode logic may be software resident in the associated 
computer system. The decode logic can provide a "beep" signal as an 
audible output upon detection of a valid read result. The visible beam and 
the "beep" signal provide feedback to the operator as to the operation of 
the scanner.