Abstract:
In an electronic camera responsive to a digital image stored in such camera and having a microfluidic printer for printing images onto a receiver to form continuous tone color pixels corresponding to the stored digital image, including focusing an image of a subject at an image plane; area image sensor disposed at the image plane for receiving the image subject and producing a digital image representing the subject; and digital storage coupled to the area image sensor for storing the digitized image of the subject. The microfluidic printer including a plurality ol colorant reservoirs including reservoirs for containing cyan, magenta, and yellow colorants, respectively, and a plurality of colorant delivery chambers, including a fourth reservoir containing a colorant modifying fluid wherein the colorant modifying fluid includes a particular scent; selectable mode control circuit responsive to the digital image for causing colorants to be delivered from colorant reservoirs to selected colorant delivery chambers in the correct amount and for delivering the colorant modifying fluid containing the particular scent from the fourth reservoir to selected delivery chambers; and the printer causing the transfer of the colorants with the selected colorant modifying fluid in the delivery chamber to the receiver to form a continuous tone color image having the desired scent.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Reference is made to commonly assigned U.S. patent application Ser. No. 08/951,017 filed Oct. 15, 1997, entitled “Camera With Microfluidic Printer” assigned to the assignee of the present invention. The disclosure of these related applications is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to electronic cameras which include microfluidic printers that produce scented prints. 
     BACKGROUND OF THE INVENTION 
     It is known in the prior art to provide an electronic camera which uses an area image sensor. Digital images produced from the image sensor are stored in memory and these images can be shown on a display so that the user can determine which image should be stored for use in producing hard copy images. Typically, these images can be stored in a magnetic disk or a compact PCMCIA Memory Card. 
     In U.S. Pat. No. 4,262,301 an electronic camera is disclosed which includes a display device. The camera also includes a digital-to-analog converter which sends signals to the display. Also, the digital-to-analog converter selectively sends these images to a magnetic tape for storage. Images on the magnetic tape can then be produced as a hard copy by a printer which is provided on the camera. A problem with the approach in U.S. Pat. No. 4,262,301 is approach is that a print must be made in order for a user to determine whether it is satisfactory. 
     A shortcoming with prior electronic cameras is that the printer is spaced from the camera and must be electrically coupled to digital storage structure within the camera which frequently produces artifacts. Another shortcoming in the prior art is that a typical print only appeals to one sense, that of sight. Memory is more effectively recalled when a plurality of senses are engaged. Scents can often trigger a favorable response in a user viewing a print and, moreover, can help the user to recall the particular time or location of the print. 
     SUMMARY OF THE INVENTION 
     An object of this invention is to provide an electronic camera with an integrated compact, low powered multimode printer which rapidly prints high quality continuous tone images and forming such images with desired scents. 
     This objects is achieved in an electronic camera responsive to a digital image stored in such camera and having a microfluidic printer for printing images onto a receiver to form continuous tone color pixels corresponding to the stored digital image, the improvement comprising: 
     a) means for focusing an image of a subject at an image plane; 
     b) area image sensor means disposed at the image plane for receiving the image subject and producing a digital image representing the subject; 
     c) storage means coupled to the area image sensor for storing the digitized image of the subject; 
     d) the microfluidic printer including a plurality of colorant reservoirs including reservoirs for containing cyan, magenta, and yellow colorants, respectively, and a plurality of colorant delivery chambers, the microlluidic printer further including; 
     i) a fourth reservoir containing a colorant modifying fluid wherein the colorant modifying fluid includes a particular scent; 
     e) selectable mode control means responsive to the digital image for causing colorants to be delivered from colorant reservoirs to selected colorant delivery chambers in the correct amount and for delivering the colorant modifying fluid containing the particular scent from the fourth reservoir to selected delivery chambers; and 
     f) means for causing the transfer of the colorants with the selected colorant modifying fluid in the delivery chamber to the receiver to form a continuous tone color image having the desired scent. 
     Advantages 
     An electronic camera with a microfluidic printer, in accordance with the present invention provides not only visually pleasing continuous tone images, but also causes a desired scent to be incorporated into such images. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram of a digital camera in accordance with the present invention with the necessary electronics for operating the camera and having a microfluidic printer which also can deliver scent to a receiver; 
     FIG. 2 is a partial schematic view showing the printer for pumping, mixing, and printing scented pixels on a reflective receiver; and 
     FIG. 3 is a top view of the colorant delivery chambers in the printer of FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Before discussing the electronic camera in accordance with the present invention, a inicrofluidic printer which is used in the camera will now be described. 
     Referring to FIG. 2, a schematic diagram is shown of a printer  8  in accordance with the present invention. Reservoirs  11   a ,  11   b , and  11   c  are respectively provided for holding colorant modifying fluid. Reservoirs  12 ,  13 , and  14  are respectively provided for holding cyan colorant, magenta colorant, and yellow colorant. These reservoirs are actually provided by colorant cartridges which are insertable into the printer  8  of the camera. A reservoir  16  is shown for black colorant. Microchannel capillaries  17  respectively connected to each of the reservoirs conduct colorant from the corresponding reservoir to an array of colorant delivery chambers  18 . In the present invention, the colorant delivery chambers  18  deliver the colorant directly to a receiver  19   a ; however, other types of colorant delivery arrangements can be used such as microfluidic channels, and so when the word chamber is described, it will be understood to include those arrangements. The colored colorants are delivered to colorant delivery chambers  18  by electrokinetic pumps  19 . The amount of each color colorant is controlled by logic and control unit  32  according to a stored digital image. For clarity of illustration, only one electrokinetic pump  19  is shown for the colorant modifying fluid channel. Similar pumps are used for the other color channels, but these are omitted from the figure for clarity. Finally, a receiver  19   a  is transported by a transport mechanism to come in contact with the microfluidic printer  8 . The receiver  19   a  accepts the colorant and thereby produce the print. 
     FIG. 3 depicts a top view of an arrangement of delivery chambers  18  shown in FIG.  2 . Each colorant delivery chamber  18  is capable of producing a mixture of colorants of different colors having any color saturation, hue, and lightness within the color gamut provided by the set of colorants used in the apparatus. This results in a continuous tone photographic quality image on the reflective receiver  19   a . As shown in FIG. 2, there is provided a logic and control unit  32  which receives a digital image. As will be discussed, the digital image is included in an image file which also includes data representative of the scent and the amount of such scent to be applied to formed image. The digital image includes a number of digital pixels which represents a continuous tone colored image. The logic and control unit  32  is connected to the electrokinetic pump  19  and controls its operation. In FIG. 2, the logic and control unit  32  includes a series of separate functional elements including central processing unit  32   a , execution memory  32   b , and program memory  32   c . A selectable mode control unit  32   d  selects the particular mode of operation which will be controlled by the central processing unit  32   a . More particularly, it causes the pump to meter the correct amount of colorants into each of the colorant delivery chambers  18  to provide both the correct hue and tone scale for each colored pixel. Another function of the logic and control unit  32  is to arrange the array of image pixels in the proper order so the image will be right reading to the viewer. The logic and control unit  32  includes a matrix, or look-up table, which is determined experimentally, of all the colors which can be achieved by varying the mixture ol colorants. When a data for a particular pixel (8 bits per color plane) is inputted, the output from the look-up table will control signals to the electrokinetic pumps  19  to meter out the correct amount of each colorant. Look-up tables are also included which are responsive to the selected scent and the amount ol such scent. The logic and control unit  32  also controls the amount of scent. Also provided is a transport mechanism  15  which is adapted to move the receiver  19   a  into and out of engagement with the colorant delivery chambers  18  under the control of the logic and control unit  32 . After the colorant delivery chambers  18  have the appropriate amount of mixed colorant, the logic and control unit  32  signals the transport mechanism  15  to move the receiver  19   a  into engagement with the colorant delivery chambers  18  for colorant transfer. 
     The colored colorants used in this invention are dispersions of colorants in common solvents. Examples of such colorants are found is U.S. Pat. No. 5,611,847 by Gustina, Santilli, and Bugner. Colorants are also be found in the following commonly assigned U.S. patent application Ser. No. 08/699,955 filed Aug. 20, 1996 entitled “Cyan and Magenta Pigment Set”; U.S. patent application Ser. No. 08/699,962 filed Aug. 20, 1996 entitled “Magenta Colorant Jet Pigment Set”; U.S. patent application Ser. No. 08/699,963 filed Aug. 20, 1996 entitled “Cyan Colorant Jet Pigment Set”, all by McInerney, Oldfield, Bugner, Bernel, and Santilli; and in U.S. patent application Ser. No. 08/790,131 filed Jan. 29, 1997 entitled “Heat Transferring Colorantjet Colorant Images” by Bishop, Simons, and Brick; and U. S. patent application Ser. No. 08/764,379 filed Dec. 13, 1996 entitled “Pigmented Colorantjet Colorants Containing Phosphated Ester Derivatives” by Martin, the disclosures of which are incorporated by reference herein. In a preferred embodiment of the invention the solvent is water. Colorants such as the Ciba Geigy Unisperse Rubine 4BA-PA, Unisperse Yellow RT-PA, and Unisperse Blue GT-PA are also preferred embodiments of the invention. The colorant modifying fluid of this invention call take a number of different forms, which will suggest themselves to those skilled in the art. If the colored colorants are water soluble, then the colorant modifying fluid can indeed be water. Concentrated fragrant oils which can be mixed with ink are known in the art and generally include natural or synthetic oils with different characteristics. They are available in different blends and are sometimes designated as highly concentrated perfumes. For a more complete discussion of such scented oils, see U.S. Pat. No. 5, 577,947, the disclosure of which is incorporated herein by reference. A fragrance of oil or blended fragrance of oils may be mixed with polymers or other additives in a manner such as disclosed in U.S. Pat. No. 4,908,252, the disclosure of which is incorporated herein by reference. 
     The reflective receiver  19   a  can be common paper having sufficient fibers to provide a capillary force to draw the colorant from the colorant delivery chambers  18  into the paper. Synthetic papers can also be used. The receiver  19   a  can have a coated layer of polymer which has a strong affinity, or mordanting effect for the colorants. For example, it a water based colorant is used, the colorant modifying fluid can be water, which also acts as a solvent, and a layer of gelatin will provide an absorbing layer for these mixed colorants. In a preferred embodiment of the invention, an exemplary reflective receiver is disclosed in commonly assigned U.S. Pat. No. 5,605,750 to Romano et al. 
     Now turning to FIG. 1, a block diagram is shown of various systems within the camera  1 . As shown, a subject S is positioned in front of the imaging lens  3 . The camera  1  includes an area image sensor  20  arranged to coincide with the axis of the imaging lens  3 . The printer  8  has been discussed. An image of the subject is focused on the area image sensor  20 . Area image sensor  20  can be a full frame charge coupled device (CCD) or, alternatively, can be an interline device with, for example, photodiode pixels which are adapted to deliver charge to interline CCDs. Conventional electronic circuitry (not shown) is associated with the image sensor  20 . After the image sensor  20  receives light representative of the image of the subject S, the circuitry sets up, acquires, and transfers electronic signals from the area image sensor  20 . Such electronics are well known in the art and their description is omitted for clarity of discussion. 
     Logic and control unit  32  causes the area image sensor  20  to transfer electrical signals to signal processor  34 . The logic and control unit  32  includes a central processing unit  32   a , program memory  32   c , and execution memory  32   b . Selectable mode control unit  32   d , which can be under the control of a user, signals the central processing unit  32   a  as to the correct mode of operation. In one mode, the printer is to apply scents from at least one of the reservoirs  11   a ,  11   b , or  11   c  into the microchannel capillaries  17  where they are delivered to the colorant delivery chambers  18  with the correct amount of scent. Alternatively, the selectable mode control unit  32   d  can signal the central processing unit  32   a  to read a digital file having a digital image to provide signals to control the delivery of scents from the reservoirs  11   a ,  11   b , and  11   c  in the appropriate amount into the microchannel capillaries  17  where they are to be mixed with the colorants from reservoirs  12 ,  13 ,  14 , and  16 . The signal processor  34  will be understood to include that circuitry necessary for converting the area image sensor signals to electrical signals and includes gain control and analog-to-digital circuitry as well known in the art. The logic and control unit  32  can, ol course, include a microprocessor as is well known to those skilled in the art. The signal processor  34  delivers, under the control of logic and control unit  32 , signals into a storage location in a temporary image memory  35  which can be either a floppy disk or semiconductor memory under the control of logic and control unit  32 . These signals, when stored, represent a digital image of the subject. The logic and control unit  32  also delivers signals to the microfluidic printer  8  which include the necessary information for controlling the amount of the colorant modifying fluid to the colorant delivery chambers  18 . The logic and control unit  32  causes the digital signals in temporary image memory  35  to be applied to a display driver  37  which, in turn, applies signals to a display device  38 . The display driver  37  will be understood to include a digital-to-analog converter and formatting control which is appropriate for the type of display device as well known in the art. The display device  38  may be embodied as a liquid crystal display. As well understood to those skilled in the art, the logical and control unit  32  provides refresh signals to the display device  38 . It will be understood that the logic and control unit  32  can also deliver the digital image to an external device such as a personal computer. 
     The logic and control unit  32  which includes the central processing unit  32   a  that may be provided by a microprocessor chip. Execution memory  32   b  is also shown and is typically provided by random access memory (RAM). This memory is used for computation during image adjustment of the various parameters. As is well known to those in this art, the program memory  32   c  (typically ROM) can include conventional image processing algorithms for changing image resolution and the color content by so-called color management programs. The selectable mode control unit  32   d  can include a keyboard, a manual switch or a combination of both, to permit a user to select the appropriate mode which, in effect, causes the central processing unit  32   a  to select the appropriate program in program memory  32   c.    
     The program memory  32   c  can include a program which can be selected by the selectable mode control unit  32   d  wherein the type and amount of scent from the reservoirs  11   a ,  11   b , and  11   c  are selected depending upon a predetermined condition such as a date or season of the year. The date can be included in a clock chip (not shown) and a program associated with the central processing unit  32   a . As noted above, the program memory  32   c  can include image processing algorithms. Many of such image processing algorithms have been implemented as commercially available packages such as: Photoshop (trademark of Adobe Systems Incorporated), Color Studio (trademark of Letraset), and PhotoMac (trademark of Avalon Development Group). For examples of color management systems including color transforms for changing color content such as contrast, brightness, and gamut, see U.S. Pat. Nos. 5,313,611 and 5,432,906, the disclosures of which are incorporated herein by reference. 
     The present invention is described in relation to a continuous tone printer. It will be understood by those skilled in the art that the term “continuous tone images” will include not only continuous tone images recorded from nature, but also computer generated images, graphic images, line art, text images and the like. It will also be understood that the term “colorant modifying fluid” refers to colorant modifying fluid or white fluids that do not absorb visible light when the colorant modifying fluid is transferred to a reflective receiver. The colorant modifying fluid must be selected so that it can readily absorb the scented materials. 
     The typical printing operation in the present invention involves the following steps. First, the selectable mode control unit  32  receives a digital image or digital image file consisting of electronic signals in which the color code values are characterized by bit depths of an essentially continuous tone image, for example, 8 bits per color per pixel. Based on the color code values at each pixel in the digital image, which define the lightness, hue, and color saturation at the pixel, logic and control unit  32  operates the electrokinetic pumps  19  to mix the appropriate amount of colored colorants and colorant modifying fluids including appropriate scent content in the array of colorant delivery chambers  18 . Stated differently, the corresponding mixed colorants in each chamber  18  are in an amount corresponding to a code value for a digital colored pixel. The mixture of colorants, which has the same hue, lightness, and color saturation as the corresponding pixel of the original image being printed, is held in the colorant delivery chamber by the surface tension of the colorant. The reflective receiver  19   a  is subsequently placed by the transport mechanism  15  under the control of the selectable mode control unit  32  in contact with the colorant meniscus of the colorant delivery chamber  18  within the printer front plate  40 . The mixture of colorants contained in the colorant delivery chamber  18  is then drawn into the reflective receiver  19   a  by the capillary force of the paper fibers, or by the absorbing or mordanting force of the polymeric layer coated on the reflective receiver  19   a . The receiver  19   a  is peeled away from the colorant delivery chamber  18  in the printer front plate immediately after the time required to reach the full density of the print. The receiver  19   a  cannot be left in contact with the front plate for too long a time or the density of the print will be higher than desired. One important advantage of the present invention is the reduction of the printing image defects that commonly occur when the cyan, magenta, and yellow colorants are printed in separate operations. Misregistration of the apparatus often leads to visible misregistration of the color planes being printed. In this invention, all the color planes are printed simultaneously, thus eliminating such misregistration. 
     Colorant from the black colorant reservoir  16  can be included in the colored in mixtures to improve the density of dark areas of the print, or can be used alone to print text, or line art, if such is included in the image being printed. 
     The construction of the printer  8  is such that a user can view the reverse side of the delivery chambers  18 . The delivery chambers  18  are fabricated in a glass member so that they can be readily observed by a user. In this way, the printer also displays an image to be printed. This is disclosed in the above referenced U.S. patent application Ser. No. 08/882,620 filed Jun. 25, 1997. As shown, a receiver  19   a  is arranged to contact the chambers and to draw colorant from such chambers by capillary action. 
     The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope ol the invention. For example, scents can be directly premixed into colorants, such as ink, and for providing a common scent for each image printed on a receiver. 
     Parts List 
     S subject 
       1  camera 
       3  imaging lens 
       8  printer 
       11   a  reservoir 
       11   b  reservoir 
       11   c  reservoir 
       12  reservoir 
       13  reservoir 
       14  reservoir 
       15  transport mechanism 
       16  black colorant reservoir 
       17  microchannel capillaries 
       18  colorant delivery chambers 
       19  electrokinetic pumps 
       19   a  receiver 
       20  area image sensor 
       32  logic and control unit 
       32   a  central processing unit 
       32   b  execution memory 
       32   c  program memory 
       32   d  selectable mode control unit 
       34  electrical signal processor 
       35  temporary image memory 
       37  display driver 
       38  display device 
       40  printer front plate 
       42  multiple images