METHOD OF AND APPARATUS FOR
HANDHELD PRINTING OF IMAGES ON A
The present invention relates generally to handheld printing devices and more specifically to handheld printing devices having "navigation" systems for determining the position of the handheld printing device with respect to the printable object.
Handheld or portable optical scanners are well known in the prior art and are designed to be moved by hand across the object or document being scanned. The handheld scanner may store the scanned image within its own memory or may be connected directly to a separate computer by a data cable which is used to store the scanned image. For example, U.S. Pat. No. 5,381,020 of Kochis, et al., for "Hand-held Optical Scanner With Onboard Battery Recharging Assembly" discloses a hand-held optical scanner which comprises a handdisplaceable scanner housing; scanner electrical components mounted within the housing for performing scanner operating functions; a battery disposed in the housing and electrically connected to the electrical components; a generator disposed in the housing and operatively associated with the battery; and a roller assembly mounted in the housing and drivingly linked to the generator. U.S. Pat. No. 5,306,908 of McConica, et al., for "Manually Operated Hand-held Optical Scanner With Tactile Speed Control Assembly" describes a hand-held optical scanner comprising an optical sensor for generating a data signal representative of a scanned object; a housing for hand-displaceably supporting the optical sensor; a roller mounted on the housing for enabling rolling displacement of the housing over a scanned object in a predetermined scan direction; a displacement sensing device for sensing the angular displacement of the roller and generating a displacement signal representative thereof; a motor drivingly linked to the roller for applying a driving torque thereto; a controller for actuating the motor responsive to the displacement signal for angularly accelerating and decelerating the roller for urging an operator to hand displace the housing across a scanned object within a predetermined speed range which is optimal for scanning.
Additionally, U.S. Pat. No. 6,002,124 of Bohn, et al, for "Portable Image Scanner With Optical Position Sensor" discloses an imaging device which may be comprise of an image head having an elongate slot therein with first and second lengthwise ends. The image head may also include a first navigation sensor aperture and a second navigation sensor aperture positioned adjacent the elongate slot at positions other than positions that are aligned with the first and second lengthwise ends of the elongate slot. An image sensing system optically aligned with the elongate slot in the image head is responsive to image light passing through the elongate slot and produces an image signal based on the image light. A first navigation sensor optically aligned with the first navigation sensor aperture in the image head is responsive to first navigation light passing through the first navigation sensor aperture and produces a first navigation data signal based on the first navigation light. A second navigation sensor optically aligned with the second navigation sensor aperture in the image head is responsive to second navigation light passing through the second navigation sensor aperture and produces a second navigation data signal based on the second navigation light. U.S. Pat. No.
6,005,681 of Pollard for "Image Scanning Device and Method" describes a method of reconstructing an image from scanned parts of an original image obtained by relative movement between a scanning device and the original image
5 so that adjacent scanned image swaths overlap. The scanning device comprises navigation means for determining the position of the scanning device relative to the original image. Navigation corrections are calculated by correlating features within the area of overlap between adjacent swaths.
10 Also related is U.S. Pat. No. 5,552,597 of McConica for "Hand-held Scanner Having Adjustable Light Pad" discloses a lens assembly which is positioned between an illuminated scanning area and a detector. Positioned between the lens assembly and the illuminated scanning area is a multiple reflecting assembly which defines a folded light
15 path between the lens assembly and the illuminated scanning area. A prismic reflecting assembly is movably mounted between the lens assembly and the multiple reflecting assembly, so that the length and direction of the folded light path can be changed by moving the prismic reflecting
20 assembly to align and focus the image of the illuminated scanning area on the surface of the detector. U.S. Pat. No. 5,586,212 of McConica, et.al., for "Optical Wave Guide for Hand-held Scanner" describes first and second elongate curved reflecting surfaces which are positioned in non25 parallel, spaced apart relation, which collect light from an elongate light source and direct the light onto a scanning area. One edge of the first curved reflecting surface is positioned adjacent the light source and the opposite edge is positioned adjacent the illuminated scan area so that the first
3Q curved reflecting surface extends from about the light source to about the illuminated scan area. The second curved reflecting surface is positioned in opposed spaced-apart non-parallel relation to the first curved reflecting surface such that the distance separating the reflecting surfaces at the light source is less than the distance separating the reflecting
35 surfaces at the end adjacent the illuminated scanning area. An elongate planar reflecting surface is positioned adjacent the second curved reflecting surface so that it is substantially perpendicular to the illuminated scan area. Some of the light rays from the light source are reflected by the first curved
40 reflecting surface and the second curved reflecting surface onto the planar reflecting surface, which in turn reflects the light rays onto the illuminated scan area so that they are incident on the illuminated scan area at substantially oblique angles. Other light rays from the light source are directly
45 reflected by either the first curved reflecting surface, the second curved reflecting surface, or by a combination of the two, onto the illuminated scan area so that they are also incident on the illuminated scan area at substantially oblique angles.
50 Each of the above described patents are assigned to the assignee of the present application and are hereby incorporated in their entirety by reference for all that they disclose.
Similarly, portable computer printers are well known in the prior art and include dot matrix printers, piezo-electric
55 inkjet printers, laser printers and thermal inkjet printers. Additionally, scanner/printer combinations are known in the prior art as are combination machines which include scanner features, printer features, facsimile machines, and document copying capabilities. However, the scanners used in these
60 combinations are relatively large desktop units serving to optically scan sheet documents transported through or placed on a scan window of the device.
A need exists for a portable printer that is adaptable to print in combination with a portable device on a desktop
65 unit. A further need exists for a compact printer compatible with a handheld device such as a personal digital assistant (PDA).