Abstract:
A portable electronic device that includes a touch screen display and a wireless communication circuitry operable at least partly in the 2.4 GHz frequency band is disclosed and enabled. The portable electronic device includes features for searching output devices using the wireless communication circuitry; displaying on the touch screen display a list identifying one or more output devices found by the searching; receiving an input supplied to the touch screen display for selecting a selected output device; and subsequently, receiving, from at least the selected output device, via the wireless communication circuitry, an output device attribute; configuring an output stream using the output device attribute; and transmitting, via the wireless communication circuitry, the configured output stream to the selected output device. The output device may be a display device, a television, a printer, an audio device, or an external controller connectable to a television.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 13/103,958, which is a continuation of U.S. patent application Ser. No. 10/016,223 filed Nov. 1, 2001, issued as U.S. Pat. No. 7,941,541, and claims benefit of U.S. Provisional Application No. 60/245,101 filed Nov. 1, 2000, the entire disclosures of which are hereby incorporated by reference herein for all purposes. 
    
    
     TECHNICAL FIELD OF INVENTION 
     Present invention relates to device synchronization and digital output and, in particular, to providing pervasive output for information apparatuses. 
     SUMMARY OF THE INVENTION 
     An Information apparatus refers to both stationary computers and mobile computing devices (pervasive devices). Examples of information apparatuses include without limitation desktop computers, laptop computers, palmtop (hand-held) computers, personal digital assistants (PDAs), Internet-enabled cellular phones, smart phones, pagers, Internet appliances, e-books, digital pads, Web pads, and digital capturing devices (e.g., digital cameras and video cameras). An output device  140  may include a fax machine, printer, copier, image or video display device, projector, and an audio output device. For simplicity and convenience, hereafter, the following description may refer to an output device as a printer and an output process as printing. However, it should be understood that the term printer and printing is used as a specific example to simplify description or may be one exemplary embodiment. The reference to printing used here is intended to be applied or extended to the larger scope and definition of output devices and should not be construed as restricting the scope and practice of present invention. 
     Fueled by ever-increasing bandwidth and processing power and ever-increasing numbers of wireless mobile devices and available software applications for pervasive devices, millions of users are or will be creating, downloading, and transmitting content and information using their pervasive computing devices. Unfortunately, the small display screen of a pervasive device may not provide a good viewing experience. As a result, there is a need to allow users to easily output content and information from their pervasive computing devices to any output device. People need to output directly and conveniently from their pervasive information apparatus, without depending on synchronizing with a stationary computer (e.g., desktop personal computer) for printing, as an example. 
     To illustrate, an information worker at an airport receiving e-mail in his hand-held computer may want to walk up to a nearby printer or fax machine to have his e-mail printed. In addition, the mobile worker may also want to print a copy of his to-do list, appointment book, business card, and his flight schedule from his mobile device. As another example, a traveler stopping at a convenience store, gas station, or kiosks may want to print out a copy of the map he just downloaded from the Internet using his Internet enable wireless phone (information apparatus). In still another example, an individual who just finished a stock trade or performed an e-commerce transaction using his PDA (information apparatus) may want to print out a copy of his transaction confirmation, invoice or receipt. In yet another example, a user who takes a picture with a digital camera may want to easily print it out to a nearby printer. 
     Conventionally, an output device (e.g., a printer) is connected to an information apparatus via a wired connection such as a cable line. A wireless connection is also possible by using, for example, radio communication or infrared communication. Regardless of whether the connection is wired or wireless, a user must first install in the information apparatus a printer driver corresponding to a particular printer model and make. Using a device-dependent or specific driver, the information apparatus may process output content or a digital document into the printer input space. The printer input space corresponds to the type of input that a printer understands (herein referred to as print data). For example, the printer input space or print data may include a printer-specific input format (e.g., image, graphics, file, data format), encoding, page description language, markup language, instructions, protocols or data that can be understood or used by a particular printer make and model. 
     Print data may be proprietary or a published standard or a combination of the two. A printer input space or print data is therefore, in general, device dependent. Different printer models may specify their own input, designed or adopted for optimal operation by the printer manufacturer according to a specification. Consequently, different printers usually require use of specific printer drivers for accurate printing. A device driver (printer driver in this example) may control, manage, communicate, and output print data to a printer. Sometimes, instead of using a printer or device driver, the device driving feature may be included as part of an application software. The application in this example may process the document and communicate directly with an output device without utilizing a device driver. Print data is an output data sent to a printer. However, the term print data used here is intended to be applied or extended to the larger scope and definition of output data which applies to any output devices including display, projection and audio devices, and this should not be construed as restricting the scope and practice of present invention. 
     Installation of a printer driver or application may be accomplished by, for example, manual installation using a CD or floppy disk supplied by the printer manufacturer. Or alternatively, a user may be able to download that particular driver or application from a network. For a home or office user, this installation process may take anywhere from several minutes to several hours depending on the type of driver and user&#39;s sophistication level with computing devices and networks. Even with plug-and-play driver installation, the user is still required to execute a multi-step process for each printer. This installation and configuration process adds a degree of complexity and work to end-users who may otherwise spend their time doing other productive or enjoyable work. Moreover, many unsophisticated users may be discouraged from adding new peripherals (e.g., printers, scanners, etc.) to their home computers or networks to avoid the inconvenience of installation and configuration. Therefore, there is a need to provide a way for a user to more conveniently or easily output digital content to an output device without the inconvenience of manually finding and installing new device drivers or printer drivers. Installation of printer drivers, if needed, should be more automatic and transparent to end-users. 
     In addition, conventional printing methods may pose significantly higher challenges and difficulties for mobile device users than for home and office computer users. The requirement for pre-installation of a device-dependent driver is in conflict with the concept of mobile (pervasive) computing and output. For example, a mobile user may want to print e-mail, PowerPoint® presentation documents, web pages, or other documents in an airplane or at an airport, gas station, convenience store, kiosk, hotel, conference room, office, home, etc. It is highly unlikely that the user would find at any of these locations a printer of the same make and model as is at the user&#39;s base station. Therefore, the user may have to install and configure a printer driver each time at each of these locations before printing. Alternatively, it is also not a viable option usually to pre-install all of the possible hundreds, or even thousands, of printer drivers available to the user&#39;s information apparatus. A mobile information device usually has limited memory and storage capacity. As a consequence, the user would currently be required to install and configure a printer driver each time at each such different location before printing. Moreover, the user may not want to be bothered with looking for a driver or downloading it and installing it just to print out one page of email at the airport. This is certainly an undesirable and discouraging process to promote pervasive or mobile computing. Therefore, a more convenient or automated printing solution is needed so that a user can simply walk up to a printer and easily print a digital document without having to install or pre-install a particular printer driver. 
     Network printing may partially solve the above problem in a local area network (LAN). Network printing was first motivated to allow people to share printing resources within a network. Printers are often connected to the network using a network adapter or network card. Print servers may be used to manage print jobs (such as spooling). Different clients may send print jobs to the print server for queuing, prioritizing and managing. The driver of each networked printer may be stored in the network (for example, in an application server) and available for clients to download. 
     The above configuration is often used in a local area network (LAN) such as in an office building. An office worker with a mobile or static computing device connected to this network may be able to send a print job to any printer that is connected to the same network. He either has the necessary printer drivers pre-installed in his device or he can download a driver from the LAN before printing to a particular printer. But once outside of the office building, or meaning outside of his wired or wireless network coverage, the office worker can no longer print to any printer he or she desires. 
     In one instance, it has been argued that the idea of local network printing can be further extended to the Internet as the larger and public network. In an ideal situation, every printer and every computing device (information apparatus) is connected to the same network, for example the Internet. But in reality, extending network printing to a big super-network or the Internet is still unavailable. 
     Nevertheless, one drawback of network printing may be higher cost. To connect the output devices and information apparatus to the same network, additional hardware or software may need to be installed. And therefore, the costs of output devices may be raised substantially. In addition to hardware and software costs there are also service charges to maintain the connectivity to a large network such as the Internet. Furthermore, a large permanent network infrastructure would need to be built and made available to each location. 
     In addition to costs, another drawback of network printing is reliability. Network printing requires perfect function in any part of the chain of network hardware, software and services. If any component of the link is down or not fully functional, for any reason, printing service may be unavailable, interrupted or result in inaccuracies. 
     Finally, another drawback of network printing is the issue of security. A user does not feel secure if confidential documents or information must pass through the entire network before reaching the printer immediately in front of him or her. There may be the fear that the confidential document could be intercepted, viewed, copied or stored within any segment of the connected network. There can also be the fear that the document could actually be printed to a different printer instead of the intended one. This problem may be caused by, for example, errors in directory service software, a software component that is not up-to-date or corrupted, inconsistent or incompatible software and/or hardware versions, or any combination of human, software, network, or hardware errors. There is also risk when downloading a software component (e.g., printer driver) from the network to an information apparatus. This software component maybe damaged, corrupted or carrying a malicious attack or virus or otherwise modified by hackers. A damaged software component can disrupt or corrupt the user&#39;s information apparatus. Finally, some internal corporate or local networks may reject unknown documents trying to reach their printers and other output devices protected within a firewall. It is therefore more desirable if the communication and exchange of information are done locally between users&#39; information apparatus and the selected output device, all within the range of the users watchful, and inspecting eyes. 
     Accordingly, the present invention provides a convenient method of digital printing in which a user need not pre-install a device-dependent printer driver on an information apparatus in order to print. 
     This invention can provide an easy, friendly and convenient process for printing. Unlike conventional printing, a user need not manually install a printer driver from a CD, floppy disk, or download it somewhere from an existing static network. With the apparatus and process of present invention, all the software components, data, or printer drivers can be loaded to the information apparatus through easy and automatic synchronization process between the information apparatus and a printer having an output controller of present invention. As a result, a mobile user with an information apparatus equipped with an output manager of present invention can print pervasively virtually at any time, anywhere, to any printer. 
     Furthermore, this invention can provide a convenient method allowing users to print to any printer with or without connection to a static permanent network for both the information apparatus and the output device. Through local communication and synchronization directly between the information apparatus and the output device, hardware and software installation for static network connectivity may not be necessary. Therefore printing costs may be reduced. 
     In addition, this invention can provide a more reliable printing method than conventional remote network printing methods or processes. By communicating locally between an information apparatus and an output device, the printing process does not depend on the perfect function of each element of a network chain. This chain may include, for example, network connections, network servers, application servers, service providers and application providers. Therefore, the chance of a successful printing under present invention is greatly enhanced as processing and communication involves fewer elements. 
     This invention can further provide a more secure printing process than conventional network printing processes and methods. Uploading or downloading data or software components such as a printer driver from an output device immediately in front of user provides a more secure feeling than dealing with components from a remote location in the network. Components stored in a large network may be perceived to have more exposure to tampering (e.g., contaminated with a virus). An erroneous module or component in the network caused by a human or software or hardware error may also disrupt the function of the information apparatus. Furthermore, sending a confidential digital document or print data directly to the printer in front of user provides a more secure feeling than if the document is routed through a large network with a plurality of users and servers. There are greater possibilities of the document being intercepted, viewed, copied, stored or finally printed on a wrong printer in conventional network printing. 
     In accordance with present invention, an electronic system and method of pervasive output allow an information apparatus to output digital content conveniently to virtually any output device. The information apparatus may be equipped with a central processing unit, input/output control unit, storage unit, memory unit, and wired or wireless communication unit or adapters. The information apparatus preferably also includes output manager that may be implemented as application software, a client application, or device driver (printer driver in case of printer). The output manager may include management and control capabilities with hardware and software components including for example one or more communication chipsets residing in its host information apparatus. 
     The output manager in the information apparatus may be capable of communicating with, managing and synchronizing data or software components with an output device equipped with an output controller of present invention. Examples of output devices include, without limitation, printers, fax machines, copiers, image or video display devices, monitors, display screens, projectors, and audio output devices. 
     The output controller may be a circuit board, card or software components residing in an output device. Alternatively, the output controller may be connected externally to an output device as an external component or “box.” The output controller may be implemented with one or a combination of embedded processor, software, firmware, ASIC, DSP, FPGA, system on a chip, special chipsets, among others. In another embodiment, the functionality of the output controller may be provided by application software running on a PC, workstation or server connected externally to an output device. 
     The output controller may include a processing unit, memory/storage unit and communication adapter unit, among others. The storage or memory unit of the output controller may store device drivers, software components or objects encapsulating device dependent data, algorithms, and code. Device dependent data may be, for example, parameters and information about the output device and output controller. Software components and objects may encapsulate for example code or executables of algorithms necessary for converting or encoding an image or document description or language into print data or output data compatible with a specific output device. The output manager may manage the process of uploading data and or software components from an output controller to an information apparatus in order to, for example, enable the information apparatus to generate and transmit print data or output data accurately to the output device or the output controller. 
     Output data (or print data in the case where the output device is a printer) may be specific data, instructions, page description language, markup language, graphics and or image file format among others. Print data may also be encoded or compressed with one or more compression or encoding techniques. Furthermore, print data may use one or more open standards or one or more proprietary techniques and formats, or a combination. Output data (or print data for printers) refers to the electronic data sent from an information apparatus to the output device. 
     One implementation of a digital content output process of this invention includes the following steps. 
     1. A user requests to print a digital content from his/her information apparatus. 
     2. The information apparatus detects available output devices by a discovery process. 
     3. The information apparatus exchanges service information with output controllers associated with the available output devices in a service negotiation process. The user may then select one or more output devices based on the service information provided. 
     4. The information apparatus communicates with output controller to identify and upload the necessary components to enable output to a specific output device as part of a synchronization process. The uploaded components or data may then be installed or configured in the information apparatus. 
     5. The digital content intended for output is processed by one or more components to be compatible with the output device. The one or more components include the information apparatus with an output manager, an output controller and the output device. 
     6. The printer engine or display engine or audio engine generates final output. 
     In the output process of present invention, an output manager residing in the information apparatus may participate in, coordinate and manage the communication and exchange of information/components between its host information apparatus and output controllers. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of an output system that can implement the process and apparatus of the present invention. 
         FIGS. 2A and 2B  are block diagrams illustrating exemplary configurations of hardware components of wireless communication units. 
         FIGS. 3A-3C  illustrates various configurations and implementations of output manager with respect to an information apparatus. 
         FIGS. 4A-4F  illustrate various configurations and implementations of output controller with respect to a printer or output device. 
         FIG. 5  is a flow diagram of a pervasive output process of the present invention. 
         FIG. 6  is a flow diagram of an exemplary implementation of service negotiation process optionally included in the output process of  FIG. 5 . 
         FIG. 7  is a flow diagram of different possible configuration of print job process included in the output process of  FIG. 5 . 
         FIGS. 8A-8G  show a series of graphical user interfaces (GUIs) rendered at different times on a display screen of an information apparatus. 
         FIGS. 9A-9B  is a block diagram of a conventional printing system or printer. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIG. 1  is a block diagram illustrating exemplary components of an electronic communication system that may provide an operating environment for the present invention and includes an information apparatus  100 , which is a computing device with processing capability. As illustrated in  FIG. 1 , examples of information apparatus  100  may include, but are not limited to, a desktop personal computer (PC), laptop computer, palmtop computer, handheld or mobile device, personal digital assistant (PDA), smart phone, screen phone, set-top box, e-book, Internet pad, digital camera, Internet appliance, pager, etc. 
     Information apparatus  100  may contain components (not shown) such as a processing unit, a memory unit, a storage unit and an input/output control unit, as are known in the art. Information apparatus  100  may also contain an interface (not shown) for interactions with users. The interface may be implemented in software or hardware or a combination. Examples of such an interface include, without limitation, a mouse, a keyboard, a touch-sensitive or non-touch-sensitive screen, one or more push buttons, soft keys, a stylus, a speaker, a microphone, etc. 
     An information apparatus  100  may be a dedicated single task device (e.g. email terminal, web terminal, e-book, etc) or a general-purpose computing device with multiple features and functions. These multiple functions and features may be implemented by one or more software applications (e.g., applications  302 ,  FIG. 3 ) installed in the information apparatus  100 , which may or may not include an operating system. A digital camera  112  equipped with processing capability and feature sets of the present invention is also an example of an information apparatus  100 . 
     Some information apparatuses  100  (e.g., dedicated devices) may be pre-configured by manufacturers with fixed functionalities and features. Other information apparatuses  100  may allow users to install additional hardware components and application software (e.g., applications  302 ,  FIG. 3 ) to expand or change functionality. Examples of functionalities and applications of information apparatuses  100  may include, for example, e-mail, messaging, voice communication, web browsing, image acquisition, text processing, graphics applications, document or image editing, and output functionalities, among others. 
     Functionalities and feature sets of an information apparatus  100  may be implemented in software or hardware or a combination of both. When features are implemented in software, this software may be installed by the manufacturer or by users. Application software may be implemented using embedded software running on embedded processors or it may run on a specific operating system. Some or all or combinations of applications and feature sets may also be implemented in hardware or in silicon. Some functionality or feature sets may be implemented in special chip sets and may include one or more or combinations of, for example, application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), systems on a chip, firmwares, etc. 
     Information apparatus  100  may or may not contain an operating system. In an implementation having an operating system, the operating system may provide a variety of application programming interfaces (APIs) or object models (e.g., APIs  300 ,  FIG. 3 ) for software applications to interface and communicate with device drivers. Device drivers in an information apparatus  100  control and communicate with peripheral devices such as printers, copiers, fax machines, display monitors, screens, etc. Several different applications can share a common device driver through the use of APIs or interfaces or object models provided by an operating system, as described below with reference to  FIG. 3A . In implementations having no operating system or an operating system that does not support or provide a device driver API, each application may have to implement its own device driver or its own output and communication capability, as described below with reference to  FIGS. 3B and 3C . For example, to output a digital document to a printer, each application may have to implement its own printer-specific driving, processing and/or communication capability. 
     In one implementation, information apparatus  100  includes an output manager  308  ( FIGS. 3A-3C ), which is typically implemented in software. Output manager  308  may be implemented or included in a client application, or as a stand-alone application, or as part of another application software  302 B ( FIG. 3B ), or in the form of a device driver (e.g., a printer driver, in case of a printer being the output device), which may be invoked, shared and used by one or more application software programs  302  ( FIGS. 3A-3C ). 
     One task for output manager  308  is to manage and coordinate communication between information apparatus  100  and one or more output controllers  120 . Output manager  308  may, for example, implement an open-standard or a proprietary communication protocol to directly or indirectly interact with, manage, or utilize functionalities provided by hardware components residing in a host information apparatus  100 . Such hardware components may include, for example, a processing unit, a memory unit and communication chipsets (not shown). Output manager  308  may include one or more of the following features and functionalities: 
     Output manager  308  may communicate and interact with one or more software applications  302  included in a host information apparatus  100  to provide pervasive output capability or feature to those software applications  302 . The type of information passed from the software applications  302  to the output manager  308  may be, for example, a digital document or digital content data that needs output. In some instances, application software  302  may invoke or launch the output manager  308  as a separate application (as shown in  FIG. 3C ) or as an integrated part of the application software (as shown in  FIG. 3B ). Examples of possible communication and management between output manager  308  and application software  302  may include, among others, messages, objects models, instances, procedural calls, program invocation and APIs, which may or may not be provided by an operating system. 
     Output manager  308  may manage and maintain wired or wireless communications with output controller  120 . Output manager  308  may interact with functionalities implemented by hardware components of its host information apparatus  100 . As an example, the output manager  308  may manage and interact with the communication unit in the information apparatus  100 .  FIGS. 2A and 2B  show an example of communication units using wireless adapters, as described below in greater detail. A user may interact with the output manager  308  through a user interlace provided by output manager  308  through the host information apparatus  100 . 
     Output manager  308  may help discover available output devices  140 , verify communication connections, identify devices available or compatible for service, or send or broadcast service requests to one or more devices. 
     Output manager  308  may communicate with output controller  120  to identify necessary software components, data, or any other device dependent information or parameters, if any, that need to be uploaded from the output controller  120  to the host information apparatus  100  to enable pervasive output. Software components may be, for example, a device driver, an application, a special code or algorithm, an executable object or device dependent data, parameter, information, etc. 
     Output manager  308  may coordinate with output controller  120  to upload the necessary components or data from the output controller  120  to its host information apparatus  100  so that the user can output digital content pervasively to that output controller  120  or its associated output device  140 . 
     Output manager  308  may perform raster image processing operations (e.g. rasterization, color management, half-toning operations) or convert digital content from its original format into print data compatible for input to a specific output controller  120  or output device  140 . The digital content may be created, stored or received by the information apparatus  100 . For example, an output manager  308  may convert digital document information from a certain format or language into a specific print data or intermediate format or language such as PostScript, PCL, EMF, XML, TIFF, JPEG, RTL, among others, for output. 
     Output manager  308  may coordinate or manage the communication between a host information apparatus  100  and output controller  120  to send or transmit the print data to the output controller  120 . 
     Output Controller  120   
     An output controller  120  may be implemented as software or hardware and may be connected to or integrated within an output device  140 . Output controllers  120 H illustrate hardware implementations in the form of a circuit board or card that is installed or integrated into an output device  140 , such as a printer, copiers, fax machine, display screen among others. In another configuration (not shown), output controller  120  may be implemented as a software application or component that is installed or integrated into an output device  140 . Output controller  120 G illustrates a hardware implementation in the form of an external component or “box” that is separately connected to one or more output devices  140 . 
     Whether externally connected to or internally installed in output device  140 , output controller  120  may be implemented with hardware, software, or both, that perform the feature sets and functionalities of the output controller  120  described herein. In the case of output device  140  being a printer, output controller  120  can also sometimes be called a printer server. Exemplary configurations and implementations of output controller  120  are described below with reference to  FIG. 4 . 
     As one example, output controller  120  may be implemented as a computer connected to one or more output devices  140 . For example, a conventional PC, workstation or server may serve the purpose of an output controller  120 . In this case, the functionalities of output controller  120  may be implemented using application software installed in the computer (PC, server, or workstation), with the computer connected to the output device  140 . 
     An output controller  120  installed or connected to an output device  140 , such as a printer, enables the output device  140  to communicate and negotiate services with information apparatus  100 . In one implementation, an information apparatus  100  may communicate with an output controller  120  connected to a printer or an output controller  120  internally installed within a printer to obtain device dependent data or software components such as device specific printer driver. An application such as an output manager  308  residing in the information apparatus  100  may install and configure the uploaded components or data, allowing information apparatus  100  to print to that printer directly. An example of an output process is described below with reference to  FIG. 5 . 
     Functionalities and feature sets of output controller  120  may include one or more of the following: 
     Provide service to clients—Output controller  120  may actively search for available clients, including information apparatus  100  or output manager  308  or other communication units, to which clients&#39; output service could be provided. Alternatively or in combination, an output controller  120  may passively wait to be discovered by one or more clients, including information apparatus  100 , to provide output service to the client or clients. 
     Negotiation of services with information apparatus  100 —Output controller  120  may communicate and exchange information with information apparatus  100  as part of negotiating the output services to be provided. As an example, in communication with an information apparatus  100 , an output controller  120  may inform the information apparatus  100  of the make, model, identification, version, type of input language, type of device driver software, type of services provided, type of components available for upload, etc. for a selected output device  140  such as a printer. As another example, an information apparatus  100  may send one or more messages to an output controller  120  inquiring about what software component or data, if any, the information apparatus  100  needs to upload from the output controller  120  to enable output to a specific output device  140 . 
     Provide security functionalities such as authentication and encryption—Authentication is used to prevent unwanted access to services, while encryption is used to prevent eavesdropping. Security procedures may be implemented by software, hardware or a combination of both, in various steps and stages of communication between the output controller  120  or the output device  140  and the information apparatus  100 . 
     Payment or transaction management and services—A user may be charged a service fee when, for example, providing output to a printer  140  or other output device  140 . Output controller  120  may have the ability to calculate and process payment according to the services requested by or rendered to a client. Output controller  120  may process payments in various forms such as cash, E-cash, credit card, debit card, E-card, smart card, virtual cash, etc. 
     Storage capability—Output controller  120  may include a memory or storage unit and may store within it one or more of the following: application software, device or printer driver, software components, device dependent data or parameters, user interfaces, etc. Software components or data stored in the output device  140  or the output controller  120  may be uploaded to the information apparatus  100  in order for the information apparatus  100  or the output manager  308  to drive the output device  140 . Software components may be executable or partially executable programs or data. 
     Synchronize with information apparatus  100 —After output controller  120  or the output manager  308  in information apparatus  100  identifies the components (software component, data, information or parameters) necessary to enable output or printing, the output controller  120  may coordinate with the output manager  308  to upload to the information apparatus  100  the components stored in a memory or storage unit of output controller  120 . 
     Provide management tools—Multiple information apparatuses  100  may request service from the same output device  140  at the same time or at overlapping times. Management tools such as queuing and spooling of print jobs, quality of service, etc. may be provided by the output controller  120 . 
     As indicated above, output controller  120  may be implemented in a variety of ways and may include hardware, software, or a combination of the two. In hardware implementations, for example, output controller  120  may include components using one or more of hardware types such as ASIC, DSP, FPGA, firmware, system on a chip, and communication chip set. Output controller  120  may also include embedded processors with software components or embedded application software to implement its feature sets, and functionalities. An output controller  120  may or may not contain an operating system. 
     Output controller  120  typically includes a memory or storage unit (ROM, RAM, flash memory, disk drive—not shown), which may store one or more software applications, software components and data. Some software applications may run in the output controller  120  to perform its functionalities (e.g., communicate with information apparatus  100 ). 
     The memory or storage unit of an output controller  120  may also store data and one or more software components that may be available to be uploaded to or synchronized with an information apparatus  100  during communication with output manager  308 . A software component may be a device driver or complete application software that can run on the information apparatus  100 . Once such a software component is uploaded and installed, the information apparatus  100  can drive or output to that specific output device  140 . 
     A software component may also be a partial device driver or partial application software or partial software component. A software component may be an executable or partially executable program, object or code. Software components may encapsulate information, algorithms, and data. Examples (of algorithms that may be included in the software components include compression/decompression methods, file conversion, graphics representation and rendering, image processing and enhancement operations, color space transformation and data conversion, encoding/decoding techniques, color matching and management methods, image transformation, interpolation methods halftoning techniques, user interface software codes etc. Examples of data that may be included in software components include, for example, a color table, color space information, halftoning tables, output device type, output resolution, bit depth, input type, format or language, communication protocol type, output status, device identification and signature, graphics, image and text descriptions etc. 
     Such software components may be uploaded to output manager  308  to facilitate communication and generation of print data or output data suitable, compatible or optimized for the output controller  120  or the output device  140 . The output controller  120  and output manager  308  manage and negotiate the proper components to be uploaded to the information apparatus  100 . 
     Not all situations require uploading an entire or complete driver or application to output manager  308  or information apparatus  100 . In some implementations uploading only a software component may be sufficient. For example, there are many inkjet printers that commonly use one-bit or multi-bit CMYK printing technology, and sometimes have similar resolutions. An information apparatus  100  may pre-install a more generic printer driver, where this printer driver contains the device independent portion of the software code, algorithms, and data that is common or can be used for this entire class of printers. Device-independent code may include, for example, a rasterization process (including half-toning and color management methods) and image enhancement of the digital document that is suitable for use with this entire class of printers. In this example, it is feasible to upload only a smaller software component or data that includes the device-dependent components for a particular printer or output device  140 . The device-dependent portion or component or data may include, but is not limited to, color tables, halftoning tables, output resolution, bit depth, compression/decompression methods, color space conversion, encoding algorithms or conversion software that is specific to that printer or output device  140 . 
     Another example of a software component stored in the memory unit of an output controller  120  for uploading to an information apparatus  100  is an installation wizard or a user interface to capture a user&#39;s preferences for printing or output operation. Examples of user preferences in the case of printing may include, without limitation, color and print quality parameter adjustments, number of copies, number of cards per page, number of pages per sheet, duplex, portrait or landscape, security information, etc. 
     Once the software components or data are uploaded or installed in information apparatus  100 , the information apparatus  100  can drive or output to the output device  140 . For example, an application  302  in the information apparatus  100  can print a digital document or image to a printer. 
     Different information apparatuses  100  may require different software components to be uploaded in order to drive a specific output device  140 . Accordingly, a variety of software components and data or device drivers for a plurality of information apparatuses  100 , operating systems, and platform types may be stored in the memory or storage components of an output controller  120 . 
     Output controller  120  may contain an embedded operating system to manage its applications. With an operating system, some or all functionalities and feature sets of the output controller  120  may be implemented as application software. Additional application software may be installed or upgraded to newer versions in order to, for example, provide additional functionalities or bug fixes. 
     Output controller  120  may contain a user interface that allows a user to configure and manage the functions provided by the output controller  120 . The user interface of the output controller  120  maybe accomplished by, for example, using display screens, soft keys, pushbuttons, mouse, stylus and keypads to allow users to interact with and manage the functions provided by the output controller  120 . Examples of such functions may include any or all of an on-off power switch, status display or indicator, cancel current job, or reorder existing jobs, etc. 
     Output controller  120  typically also includes a communication or adapter unit, which allows output controller  120  to communicate with other devices including information apparatus  100  through wired or wireless connections. Exemplary configurations of wireless adapter or communication unit are described below with reference to  FIG. 2 . 
     When output controller  120  is implemented as firmware, or an embedded application, the configuration and management of the functionalities of output controller  120  may be optionally accomplished by, for example, using controller management software in a host computer (not shown). A host computer may be a desktop personal computer (PC), workstation, or server. The host computer may be connected locally or through a network to the output device  140  or controller  120 . Communication between the host computer and output controller  120  can be accomplished through wired or wireless communication. The management application software in the host computer can manage the settings, configurations, and feature sets of the output controller  120 . Furthermore, a host computer configuration application may download or install application software, software components or data in the output controller  120  for the purpose of upgrading, updating, and or modifying the features and capabilities of the output controller  120 . 
     Output device  140  in one implementation includes or is connected to output controller  120  described above. Therefore, functionalities and feature sets provided by output controller  120  are automatically included as part of the functionalities of output device  140 . The output device  140  may, however, implement or include other controllers or applications that provide at least partially the features and functionalities of the output controller  120 . 
     Therefore, the output device  140  may include some or all of the functionalities and feature sets provided by the output controller  120 . 
     Output Device  140   
     Output device  140  is an electronic system capable of outputting digital content regardless of whether the output medium is a substrate (e.g., paper), a display image, a projection, or sound. A typical example of output device  140  may be a printer, which outputs digital documents containing text, graphics, images or any combination onto a substrate. Output device  140  may also be a display device capable of displaying still images or video, such as, without limitation, televisions, monitors, and projectors. Output device  140  can also be a device capable of outputting sound. Any device capable of playing or reading digital content in audio (e.g., music) or data (e.g., text or document) formats is also a possible output device  140 . A printer (including a fax machine, copier, etc.) is frequently referred to herein as the exemplary output device  140 . However, it should be recognized that the present invention applies as well to output devices  140  other than printers. 
       FIG. 9A  is a block diagram of a conventional printing system or printer  900 A having three basic components: raster image processor (RIP)  902 , a memory buffer  904 , and a marking engine  906 . Raster image processor  902  converts digital content into a bitmap suitable for printing; memory buffer  904  holds the rasterized image ready for printing; and marking engine  906  transfers colorant to a substrate (e.g., paper). 
     Marking engine  906  may use any of a variety of different technologies to transform a rasterized image to paper or other media or, in other words, to transfer colorant to a substrate. The different marking or printing technologies that may be used include both impact and non-impact printing. Examples of impact printing may include dot matrix, Teletype, daisywheel, etc. Non-impact printing technologies may include inkjet, laser, electrostatic, thermal, dye sublimation, etc. 
     Marking engine  906  and memory buffer  904  of a printer  900  form its printer engine  908 , which may also include additional circuitry and components, such as firmware, software and or chips or chipsets for decoding and signal conversion etc. (not shown). Input to a printer engine  908  is usually a final rasterized print data generated by the raster image processor  902 . Such input is usually device dependent and printer specific. The printer engine  908  may take this device dependent input and generate output pages. 
     Raster image processor (RIP)  902  may be located within the printing device itself (as shown in  FIG. 10A ) or externally implemented as hardware, software, or a combination. As an example, RIP may be implemented in a software application or device driver in the information apparatus. A RIP may also reside within a printer controller, a print server or an output controller of present invention. Examples of raster image processing operations may include image and graphics interpretation, rasterization, segmentation, color space transformation, image enhancement, color correction, halftoning etc. 
     When a RIP  902  is located inside an output device  140 , the RIP  902  is usually included in a printer controller  910  that may, for example, interpret, convert and/or rasterize input print data into a final format, language or instructions that printer engine  908  can understand. A laser printer with a faster printing speed is an example that falls in this category. For example, a PostScript printer controller  910  may contain a postscript interpreter (not shown) and a raster image processor  902  (RIP). Postscript interpreter interpret the postscript language and the raster image processor  902  may process the digital document and converting it to a printer specific format, language or instructions that can be accepted by the printer engine  908 . In this example, a device-dependent printer driver (e.g., a Postscript driver, not shown) may be needed in the information apparatus  100  to convert digital document from its original format into print data (e.g. in PostScript) that is acceptable to the printer controller  910 . 
     Another example of page description language is PCL (Printer Command Language) from HP (Hewlett Packard). In the same way as postscript, a printer equipped with PCL printer controller  910  can take PCL as input. Information apparatus  100  usually needs to have PCL printer driver in order to drive or print to a printer equipped with a PCL controller. 
     Although the illustrations above use PostScript and PCL as examples, a variety of other page description languages, markup languages, image formats, graphics formats, and file formats may also be used as input print data  920  to a printer  900  or output device  140 . Examples of possible inputs other than PostScript and PCL may include without limitation, EMF, XML, HTML, among many others. Some printer manufacturers may also use a combination of proprietary or nonproprietary page description languages, markup languages, file formats, graphics and image formats, color spaces, metafiles, encoding, decoding, compression or decompression etc. for the print data  920 . Print data  920  sent to printers with printer controllers  910  are usually intermediate descriptions of a digital document that may require further interpretation, processing and/or conversion before it can be send a printer engine for output. A printer controller  910  may interpret and process the input intermediate print data information into the final format that can be understood by the printer engine  908 . Regardless of the type of print data  920 , users usually have to pre-install a device-specific driver in their information apparatus  100  in order to output the proper language, format, or file that can be accepted by a specific printer  140 . 
     Some output devices  900 B do not have a printer controller  910  as shown in  FIG. 9B . A typical example is a lower-cost inkjet printer. RIP in this example may be implemented in a software application  302  or device driver or output manager  308  of present invention in the information apparatus  100 . Therefore, the rasterization process may occur in the information apparatus  100  that outputs to such a printer. A device-specific driver or application may need to reside in the information apparatus  100  to rasterize and convert the digital document from its original format into final print data  920 B (e.g., compressed CMKY data with one or more bits per pixel) that can be understood by a particular printer engine  908 B. 
     In present invention, for the printer  900 B, RIP can be integrated within the output manager  308  or application software  302  in the information apparatus  100 . Alternatively, RIP may also be integrated as a part or a function of any one of output controllers as shown in configurations  120 D,  120 E, and  120 F. 
     The output controller  120  may be connected externally to an output device  140  or integrated internally into the output device  140 . If an output device  140  such as a printer already includes a printer controller  910 , the output controller  120  may be implemented serially or cascaded with the printer controller  910  as two separate controllers. Alternatively, output controller  120  can be integrated with a printer controller to become a “combined controller”  120 C. A combined controller (e.g.,  120  C or  120 F) has functionalities of both printer controller  910  (e.g., input interpretation and or raster image processing) and output controller  120  of the present invention. Other configurations and implementations of output controller  120  and printer controller  910  are also possible. The various possible configurations and implementations of output controller are described below with reference to  FIG. 4 . 
     Communication Unit 
     Communication links  150  and  160  between information apparatus  100  with an output controller  120 , whether externally connected and or internally integrated, may be variously implemented. In one implementation, information apparatus  100  communicates with output controller  120  through wireless connections such as infrared or radio links. Examples of wireless connections technology include without limitation IrDA, home RF, Bluetooth, IEEE 802.11, HiperLan2, among others. However, wired connections such as serial interfaces, parallel interfaces, USB interfaces, Fire Wire (IEEE 1394), Ethernet and token ring network among others may also be implemented in the present invention. Adapter pairs may be incorporated into each communicating node (e.g., information apparatus  100  and output controller  120 ) to conduct communications by performing signal conversions. 
     In the case that output controller  120  is installed as an external component or “box” (as shown in  FIG. 4A ), the communication link  170  between output controller  120  and output device  140  may also be implemented using wired or wireless adapters. 
       FIGS. 2A and 2B  are block diagrams illustrating two exemplary configurations and implementations of wireless communication adapters that may be included in an information apparatus  100 , output controller  120  or output device  140 . Referring to  FIG. 2A , a radio adapter  200  may be implemented to enable data/voice transmission among devices through radio links. A RF transceiver  214  coupled with antenna  216  is used to receive and transmit radio frequency signals. The RF transceiver  214  also converts radio signals into and from electronic signals. The RF transceiver  214  is connected to a RF link controller  210  by an interface  212 . The interface  212  may perform functions such as analog-to-digital conversion, digital-to-analog conversion, modulation/demodulation and other data conversion functions. 
     RF link controller  210  implements real-time lower layer (e.g., physical layer) protocol processing that enables the hosts (e.g., information apparatus  100 , output controller  120 , output device  140 , etc.) to communicate over a radio link. Functions performed by the link controller  210  may include, without limitation, error detection/correction, power control, data packet processing, data encryption/decryption and other data processing functions. 
     A variety of radio links may be utilized, including a group of competing technologies operating in the 2.4 GHz unlicensed frequency band. This group currently includes Bluetooth, Home radio frequency (Home RF) and implementations based on the IEEE 802.11 standard. Each of these technologies has a different set of protocols and they all provide solutions for wireless local area networks (LANs). Interference among these technologies could limit deployment of these protocols simultaneously. It is anticipated that new local area wireless technologies may emerge or that the existing ones may converge. Nevertheless, all theses existing and future wireless technologies may be implemented in the present invention to transmit data between different devices without limitation and therefore in no way depart from the scope of present invention. 
     Among the current available wireless technologies, Bluetooth requires relatively lower power consumption. Bluetooth has its own protocol stack and is designed for short range (10 meters), point-to-multipoint voice and data transfer. It is based on a frequency-hopping version of spread spectrum. Seventy-nine hop frequencies are utilized beginning at the lowest frequency of 2402 MHz and each of the 79 hop frequencies is 1 MHz above the next lower frequency. Bluetooth-enabled devices operate in piconets, in which several devices, using the same hopping pattern or sequence, are connected in a point-to-multipoint system (piconet). One device (master) in each piconet determines how the bandwidth is allocated to other devices (slaves). As many as 10 piconets of 8 devices each can operate simultaneously. 
     Referring to  FIG. 2B , infrared (IR) adapters  220  may be implemented to enable data transmission among devices through infrared transmission. The IR adapters  220  may be conveniently implemented in accordance with the Infrared Data Association (IrDA) standards and specifications. In general, the IrDA standard is used to provide wireless connectivity technologies for devices that would normally use cables for connection. The IrDA standard is a point-to-point (vs. point-to-multipoint as in Bluetooth), narrow angle, ad-hoc data transmission standard designed to operate over a distance of 0 to 1 meter and at speeds up to 4 Mbps. 
     Configuration of infrared adapters  220  may vary depending on the intended rate of data transfer.  FIG. 2B  illustrates one embodiment of infrared adapter  220 . Transceiver  226  receives/emits IR signals and converts IR signals to/from electrical signals. A UART (universal asynchronous receiver/transmitter)  222  performs the function of serialization/deserialization, converting serial data stream to/from data bytes. The UART  222  is connected to the IR transceiver  226  by encoder/decoder (ENDEC)  224 . This configuration is generally suitable for transferring data at relatively low rate, for example 115.2 kbps or below. Other components (e.g. packet framer, phase-locked loop) may be needed for higher data transfer rates. 
       FIGS. 2A and 2B  illustrate exemplary configurations of wireless adapters. Such adapters are implemented into devices (e.g., information apparatus  100 , output controller  120 , output device  140 , etc.) to enable wireless communications among/between them. Wired links, however, such as parallel interface, USB, firewire interface, Ethernet and token ring networks may also be implemented in the present invention by using appropriate adapters and configurations. 
     Different Output Manager Configurations and Processes 
       FIGS. 3A-3C  illustrate different implementations of output manager  308 .  FIG. 3A  shows an exemplary configuration of output manager  308  in which its host information apparatus  100  includes an operating system. Such information apparatuses  100  may include, without limitation, desktop PC, laptop PC and handheld or palmtop computer, among others. The operating system provides API&#39;s or object models  300  for software applications  302  to interface and communicate with various device management applications sometimes called device drivers. Output manager  308  in this case may be characterized as one of the device management applications or device drivers. Different software applications  302 A can share the same output manager  308  through the use of API&#39;s  300  provided by an operating system. 
     As shown in  FIG. 3A , email application  302  A 1 , document creation application  302  A 2  and Internet browsing application  302  A 3  (referred to generally or together as application software  302 ) may operate on top of or through an operating system included in the information apparatus  100 . The operating system provides or supports API&#39;s or object models  300  for these software applications  302  to communicate with and access utilities and services provided by output manager  308 . Application software  302  and output manager  308  may communicate with each other through a variety of means using for example file transfer, metafile, messages, instances, procedural calls, etc., which may or may not be provided by the operating system or its API&#39;s or object models  300 . The output manager  308  communicates and synchronizes with output controller  120  to enable pervasive output. Therefore, a user may output digital contents from any of these software applications  302  (email, document creation, Internet browsing, etc.) to an output device  140  equipped with or connected to output controller  120 . 
     It should be recognized that the three software applications  302 ( 1 )- 302 ( 3 ) illustrated in  FIG. 3  are merely examples of applications that may be included in the information apparatus  100 . Various other software applications  302  (e.g., messaging, digital imaging, graphics, video, audio, etc.) may also exist in the same information apparatus  100  and they may all access the utilities provided by the output manager  308 . It should also be recognized that other device management applications or drivers might also be included in the information apparatus  100 . These device management applications or drivers may be implemented in the same way as output manager  308  so that they can be accessed by other software applications supported by the operating system. 
       FIGS. 3B and 3C  illustrate exemplary configurations of output manager  308  when information apparatus  100  includes, respectively, no operating system or a less capable operating system that does not provide API&#39;s or object models  300  for software application  302  interactions. Examples of such an information apparatus  100  may include, without limitation, PDA, smart phone, pager, Internet pad, email terminal, digital and video cameras, ebook and other dedicated devices etc. In this case, each software application  302  in the information apparatus  100  provides or implements the capabilities to enable pervasive output. As shown in  FIG. 3B , each software application  302  B 1 - 302  B 3  integrates output manager  308  or includes the features of output manager  308  to enable pervasive output. It should be recognized that, even in an environment where there is a complete operating system, application software  302  can still decide to implement its own output or device management capabilities (as shown in  FIG. 3B ) and not depend or use the functionalities or API&#39;s or object models  300  provided by an operating system to facilitate access of output manager as a separate application. 
     Instead of integrating the output manager  308  into application software  302 , an alternative implementation is shown in  FIG. 3C . The software applications  302  C 1 - 302  C 3  may establish direct links with the output manager  308 , which may be used as a helper program that can be invoked or launched by each software application  302  as needed. 
     The communication and exchange of information between output manager  308  and other software applications  302  can be accomplished by one or more of many available techniques, such as passing, transferring or exchanging objects, messages, procedural calls, files, metafiles, etc. Some of these techniques may be facilitated by a set of APIs or object models provided by the application software  302  or output manager  308  or the operating system. The exact technique may depend for example on the type of application, platform, language, and developer preference etc. This may be easily implemented and recognized by an average software engineer skilled in the art. 
     The above are merely exemplary implementations of output manager  308 . Due to the diversity of feature sets and capabilities of operating systems, other implementations of output manager  308  are also possible. As an example, some operating systems may provide partial APIs or object models to support limited output capability. In this case, software applications  302  may rely on the limited output capacity to interact with device management applications, or the software applications  302  can implement or incorporate partially other desired output features of the output manager  308  using the configurations or combination of configuration illustrated in  FIG. 3B  or  3 C. 
     Different Output Controller Configurations and Processes 
       FIGS. 4A-4F  illustrate various alternative configurations and implementations of output controller  120 . As described above, a printer  900 A ( FIG. 9 ) may include within it a RIP  902  or printer controller  910 . Such printer  900 A is usually more powerful and therefore more expensive than printers without these features. One example of such printer  900 A is high-speed laser printer. Output controller  120  may be variously implemented in printers regardless of whether they include a printer controller. 
       FIG. 4A  shows that output controller  120  may be cascaded externally to one or more printers (only one shown). Information apparatus  100  communicates with output controller  120 A, which then communicates with output device such as a printer  104 A. The communication link between the output controller  120 A and the printer  140 A may be a wired link or a wireless link, as described above. 
       FIG. 4B  shows another implementation in which output controller  120 B is installed as one or more circuit boards or cards internally inside printer  140 B. The output controller  120 B may co-exist with printer controller and other components of the printer  140 B. One example of this implementation is to connect output controller  120 B sequentially with the printer controller. 
       FIG. 4C  show a third implementation in which the functionalities of output controller  120  and printer controller  910  are combined into a single controller (—referred to as “combined controller”)  120 C. The combined controller  1200  is a more capable controller. In this implementation, it is possible to reduce the cost of material when compared to implementing two separate controllers as shown in  FIG. 4B . As an example, the combined controller  1200  may share the same processors, memories, and storages to run the applications and functionalities of the two types of controllers and therefore, may have lower component costs when compared to providing two separate controllers. 
     Some printers do not include a raster image processor or printer controller  910 , as illustrated in  FIG. 9B , and as a result are usually less expensive. An example of this type of printer is a low-cost desktop inkjet printer. This type of printer may use a proprietary or published input format. For example, the input to an inkjet printer may consist of specific proprietary compressed CMYK data with one or more bits per pixel input. Application software  302  or printer drivers included in information apparatus  100  usually perform raster image processing. It is therefore necessary that the proper device driver or application software runs the raster image processing on an information apparatus  100  before printing. Accordingly, output controller  120  may be implemented into a variety of printing systems, including printers without capable or complete printer controllers for performing raster image processing functions. 
       FIG. 4D  shows as a fourth implementation of output controller  120 D that is installed in an external component or “box,” which is connected to a printer  140 D that does not include a printer controller or raster image processor. In this configuration, an application software  302  or device driver  308  in information apparatus  100  would typically perform the rasterization function. However, some or all operations of raster image processing may also be implemented in the output controller  120 D. Any print data sent to the printer  140 D from the output controller  120 D is preferred to be in a final format that can be understood and processed by the printer engine of the printer  140 D. As in other examples, connection between output controller  120 D and output device  140 D can be wired or wireless. Connection between information apparatus  100  and output controller  120 D is preferred to be wireless, for example. 
       FIG. 4E  shows as a fifth implementation of an output controller  120 E that is incorporated within printer  140 E as one or more circuit boards or cards and may contain software and applications running on an embedded processor. As with printer  140 D ( FIG. 4D ), printer  140 E does not include a printer controller or raster image processing capability. Accordingly, information apparatus  100  would typically perform rasterization functions in this implementation. However, raster image processing could alternatively be provided completely or partially by output controller  120 E, for example, to speed up raster image processing operations for an information apparatus  100  having limited processing and memory capabilities. 
       FIG. 4F  shows a sixth implementation, a combined controller  120 F that integrates the functionalities of a printer controller and an output controller into a single external combined controller component or “box”  120 F. The two controller functions may share a common processor as well as a common memory space to run applications of the two types of controllers. Under this configuration, either information apparatus  100  or the combined controller  120 F could perform or share raster image processing functionality. One exemplary implementation of the combined controller  120 F shown in  FIG. 4F  is to use an external computing device (PC, workstation, or server) running one or more applications that includes the functionality of output controller  120  and printer controller  910 . 
     The above are exemplary implementations of output controller  120 , but other implementations are also possible. For example, partial functionalities of output controller  120  may be implemented in an external “box” while the remaining functionalities may reside within an output device  140  as a separate circuit board or integrated with a printer controller. As another example, the functionalities of output controller  120  may be implemented into a plurality of external boxes connected to the same output device  140 . As a further example, the same output controller  120  may be connected to and service multiple output devices  140 . 
       FIG. 5  illustrates one embodiment of output process using a printer as primary output device  140 . It should be recognized, however, the following described process can be similarly applied to other output devices  140  such as fax machines, digital copiers, display screens, monitors, TVs, voice output devices, etc. 
     Step  500  indicates that a user initiates output from an information apparatus  100 . For example, a user may want to print or otherwise output an email, receipt, confirmation, map, photo, graphics, web page, one or more slides of a PowerPoint®-brand presentation, or any other document or digital content from an information apparatus  100 . The output may be initiated by various means, such as by using a soft key, push button, keyboard, keypad, mouse, stylus, software GUI, command or voice activated command, etc. An exemplary user interface with which a user may initiate such a process from an information apparatus  100  is described below with reference to  FIG. 8 . Step  500  and one or more other steps of output process, shown in  FIG. 5 , may be implemented by an output manager  308  residing in a user&#39;s information apparatus  100 . 
     Step  502  references a discovery process in which, for example, information apparatus  100  searches for available output devices  140 , including display devices, printers, copiers or fax machines among others (collectively refer to as “printers” here for simplicity of discussion), that can perform a requested output or print job. The output manager  308  residing in the information apparatus  100  may participate in, coordinate and manage the discovery process  502 . As part of discovery process  502 , information apparatus  100  may communicate via a wired or wireless connection with output controllers  120  that are connected to or included in output devices  140 . 
     In some situations, the discovery process  502 , or part of it, may be skipped. For example, discovery process  502  may be skipped if a user already knows the output device or printer to which output is to be directed. As another example, a user may set a frequently used printer as a preferred default printer so that discovery process  502  may be partly skipped if the default printer is found to be available. Other examples in which discovery process  502  may be optional or partly skipped involve direct wire line connections or infrared communications. In these cases, a user may directly connect or physically point an information apparatus  100  to a specific output device  140  so that it could be sufficient only to check the connection and establish communication between the devices. 
     Discovery process  502  may operate in a variety of scenarios. In one scenario, information apparatus  100  broadcasts a service request, for example printing, through wired or wireless signals. Service devices, such as output device  140  equipped with output controller  120 , “listen to” such signals, “read” the request, “see” whether they can provide requested service, and respond if they can provide the requested service. Alternatively or in combination, all service devices can periodically or continuously announce or advertise the services they provide. Information apparatus  100  “listens to” such announcements and identifies the service it needs. In a third scenario, service devices of the same network (e.g., LAN) register their services with a control point. A control point is a computing system (e.g. a server, controller) that maintains records on all service devices within the same network. Information apparatus  100  may contact the control point to search for the service it needs. 
     Various protocols may be implemented in the discovery process  502 . Wireless communication protocols are preferred. Wired communication, on the other hand, may also be implemented. Examples of applicable protocols may include, without limitation, Bluetooth, HAVi, Jini, Salutation, Service Location Protocol, and Universal Plug-and-play, among others. Other proprietary protocols or combinations may also be implemented in the discovery process. 
     In the discovery process  502 , information apparatus  100  may or may not find an output device  140  available to accept its print or output job. Exemplary factors that may impact the availability of output devices  140  may include, without limitation, the following: 
     Physical distance—Some wireless communication links may impose limitations on physical distance between communicating devices. The restrictions on physical distance may vary among different wireless communication technologies. Wired communication, on the other hand, is also subject to the availability and length of cable or other wired lines. 
     Compatibility—The output process with reference to  FIG. 5  employs communication and coordination among various devices such as an information apparatus  100  having output manager  308 , and output controllers  120  associated with output devices  140 . Compatible hardware and software components may need to reside in each of the communicating nodes (e.g., information apparatus  100  and output device  140 ). Any missing part may cause compatibility problems. Other factors may also cause lack of compatibility. For example, components stored in the memory unit of output controller  120  may not support the operating system or application software  312  included in the information apparatus  100 . 
     Security authentication—Security authentication may be implemented in various steps of communication, including the discovery step  502 . Security authentication may be required for example when an output service is restricted to a certain group of users or information apparatuses. When a user requests service, output device  140  or output controller  120  may process an authentication step by automatically detecting the identification or other information provided by the user, output manager  308  or information apparatus  100 . As a result of such an authentication process, the information apparatus  100  of a particular user may not be able to discover an available output device  140  because access is not authorized for the user or the apparatus. 
     User specified search criteria—The user may specify certain search criteria for discovery process  502 , such as output device model, quality of service provided, range or price of service charge, etc. Output devices  140  not satisfying user criteria or a default profile may not be shown to the user. 
     Step  506  indicates that the user is notified if no available output device  140  is found in the discovery process  502 . The user may be notified by an application such as the output manager  308  through a user interface of the information apparatus  100 . The information apparatus  100  may also provide more detailed information such as the reasons why the requested service is not available. Examples of possible reasons may include, among others: no output device within limited physical distance, no compatible hardware or software components, technical difficulties, security authentication not satisfied, no subscription to the service, search criteria not met, etc. 
     Step  508  indicates that alternatives are provided when a requested service is not available at the current moment. The user may be provided with alternatives such as canceling the service request, trying again, or being notified when the requested service is available or the requested output device  140  is identified or becomes available. As an example, the user&#39;s information apparatus  100  may not detect any available output devices  140  in the current wired/wireless network. The print requests are then queued or registered within the information apparatus  100 . When the user enters a new network having available printers, or when new compatible printers are added to the current network or when a printer becomes available for any reason, the user would be notified of such availability through the information apparatus  100 . The user may then output the print job to the newly detected or now available printer with, for example, a mere click of a button. This detection and notification function may be implemented by a software program or as a feature of the output manager  308 . This feature may also be implemented in hardware or combination of hardware and software residing in the information apparatus  100 . 
     Step  514  indicates that service negotiation is performed, such as when one or more available printers are discovered in the discovery process  502 . In service negotiation process  514 , information apparatus  100  exchanges information with output controllers  120  connected to or installed in the available output devices  140 . The output manager  308  may participate in, coordinate or manage negotiation process  514  with output controller  120 . Information being exchanged may include, for example, the following: 
     Type, make and model of each available output device  140 , including information about the printer engine, its technology and specifications of the output device. 
     Type and parameters of the output device  140  such as font or international character code supported, paper size, resolution, bit depth, color space, number of colors supported, color or grayscale etc. 
     Type of service and quality of service provided by each available output device  140 . 
     Conditions under which the services are provided (e.g., service charge, subscription charge) and whether, for example, transaction and service charges are satisfied. 
     Whether the usage or service of each output device  140  is restricted to certain groups, in which case the user may have to provide authentication information to be identified as member of such a group before use of that device is allowed. 
     Type, make and model (including operating system) of the information apparatus  100 . 
     The type of input format, encoding, language, data, color space, and or compression that the output controller  120  or other device may take as input, for example, PostScript, PCL, RTL, XML, etc. 
     The type of component or data that may need to be uploaded from output controller  120  to information apparatus  100  so as to enable output to a specific output device. 
     The information being exchanged may be entered manually by the user or may be automatically detected and or synchronized between the information apparatus  100  and the output controller  120  or it may be partially assisted by the user or partially automated. Some or all of the information being exchanged may be provided to the user through a user interlace in the information apparatus  100 . The user may monitor the status or approve certain transactions. One embodiment of the service negotiation process  514  is described below with reference to  FIG. 6 . Based on the information provided and obtained in the service negotiation process  514 , the user may choose one or more output devices  140  that can take the print or output job. 
     Step  516  indicates that a synchronization process is performed once an output device  140  has been identified and selected. Before synchronization process  516  begins, the information apparatus  100  may communicate with the output controller or controllers  120  of the selected output device or devices  140  to identify what components, if any, need to be uploaded to the information apparatus  100  to enable printing or other output. This communication between information apparatus  100  and output controller or controllers  120  may not be necessary if adequate information has been obtained in the discovery process  502  and or service negotiation process  514 . Synchronization process  516  may be optional or it may be partially skipped if the necessary components (e.g., identified in the service negotiation step  514 ) already exist in information apparatus  100 . 
     After they have been identified, the necessary components or parts of components or data may be uploaded to the information apparatus  100  from output controller  120 . Examples of possible components may include, without limitation, one or more of the following: data, device driver, printer driver, application software, software components, metafiles, user interface etc. The output manager  308  may participate in, coordinate or manage the synchronization process  516 . Encryption techniques may be implemented in the synchronization process  516  to prevent eavesdropping. 
     The newly uploaded components may be incorporated into the output manager  308  residing in the user&#39;s information apparatus  100 . Alternatively or in combination, the newly uploaded components may be installed into the information apparatus  100  as a separate application or as part of the output manager  308 . The process of uploading and installing may be done automatically or manually by the user, or a combination of the two. 
     Part or all of synchronization process  516  may be skipped in some instances. For example, the information apparatus  100  may already include all the software components and data or drivers necessary for output to the selected output device or devices  140 . This may be due to the components having been uploaded from a previous synchronization process  516  and left undeleted, or alternatively the user may have preinstalled all the necessary components for output in the information apparatus  100 . In these cases, no software components are being uploaded and the user may be notified of this status for possible override of synchronization process  516 . Alternatively synchronization process  516  may be automatically skipped transparently to the user. 
     Step  518  indicates that print or output job processing is performed. In this step  518 , the print request or print job is processed and digital content or document may be converted to the final format to send to the output device  140  for output. At the beginning of this step  518 , the user may be provided with options to select or change or input printing or output preferences such as page layout, number of copies, color/grayscale, print quality parameters, etc. These options may include or offer pre-configured user preferences or factory defaults. Some options, parameters and preferences may be device-dependent while others may be device-independent. For example, device dependent parameters and preferences may be presented after having synchronized or uploaded device dependent components or information from the output controller  120 . Device independent parameters and preferences may also be uploaded and synchronized like the device dependent parameters and preferences or may be pre-installed as part of the output manager  308  prior to the synchronization and uploading of information. 
     With reference to  FIGS. 4A-4F , output controller  120  may be implemented in a variety of ways. Different implementations of output controller  120  may impact the procedures described here. The original digital document or content included or generated in an application  312  in information apparatus  100  may be processed by different applications in different locations (application software  312 , output manager  308 , output controller  120 , printer controller) before being converted to a final print data that can be accepted by a printer engine for output. For example, raster image processing of the digital document to convert it to print data suitable to output device  140  may occur entirely or partially in application software  312 , output manager  308 , output controller  120 , or the printer controller, depending on the implementation, configuration, and the type of output system and output device among others. Different processing procedures and embodiments that may be implemented in this step  518  are described in more detail below with reference to  FIG. 7 . 
     Step  520  indicates that the printer engine or display engine  908  generates a final output. In this step  520 , the processing result of step  518  is sent to a printer engine or display engine  908  of an output device  140  to generate final output on a substrate, for example. Memory buffers may be needed to temporarily store print data before output. Firmware, DSP, ASIC, FPGA, system-on-a-chip, software, or a combination, may be used or involved to convert digital data into signals suitable for the printer engine or display engine  908 . 
     After a print job or output job has been successfully printed or displayed, the user may be provided a choice (not shown) to delete the components that have been uploaded to the information apparatus  100  during the synchronization process  516 . This optional feature may be useful when the information apparatus  100  has limited storage space. One implementation of this optional feature is to provide a setting in the output manager  308  in which the user has a choice to (1) always keep the uploaded data or components; or (2) always automatically delete the uploaded data or components upon completion of the print job, or upon exit of the application, or upon shutting down of the information apparatus or upon elapse of certain amount of time; or (3) always ask the user whether to delete or keep the uploaded component or data. 
     The above description illustrates an exemplary embodiment of output process  501 . A printer is referred to as output device  140  in the above illustration, however, it should be recognized that output process  501  could be easily applied to other output devices  140  such as fax machines, digital copiers, display screens, TVs, monitors, projectors, voice output devices etc. 
     A pervasive output process implementing fewer or additional steps may also be possible. For example step  502 , the discovery process, may be skipped if the user already knows which printer or printers are to output the content. As another example, a payment-processing step may be added to the above-described output process  501  if the printing service is provided for a fee. Output controller  120 , in this case, may provide services such as calculating payment amount or collecting payments in a variety of possible forms, for example, credit card, bank card, cash, E-cash, smart card, among others. The payment information (e.g., credit card number or other credit identification or payment) may be stored in the information apparatus  100  and released to the output controller  120  at the user&#39;s choice. Adding additional processes or skipping one or more steps in output process  501  does not, however, depart from the spirit and scope of present invention. 
       FIG. 6  illustrates an embodiment of service negotiation process  514 . In this illustration, it is assumed that available output devices  140  have been identified from the discovery process  502 . In the service negotiation process  514 , information apparatus  100  exchanges information with output controller  120  or output devices  140 . Service negotiation process  514  may include one or more of the following: 
     (1) The user may be provided with information on the available output devices  140 . 
     (2) The user may select a desired output service according to the information provided. 
     The output manager  308  residing in the information apparatus  100  may participate in, coordinate and manage the service negotiation process  514 , together with the output controller  120 . 
     In step  600 , the user may be provided at information apparatus  100  with information on some or all available output devices  140  identified in the discovery process  502 . Information being provided here may include one or more of the following: 
     Total number of available output devices discovered. 
     Model and make of each available output device. 
     Type and capability of the output device. 
     Type of service and quality of service provided by each available output device. 
     Conditions under which the services are provided. For example, if service charge or subscription fee is required and the acceptable payment method. 
     Whether the use of each output device is restricted to certain groups. 
     The components or information, if any, need to be uploaded to the information apparatus to enable output to the selected output devices. 
     Information collected during discovery process  502  may be provided to the user through a user interface on the information apparatus  100 , such as a GUI or voice or another interlace. 
     In step  602 , based on some or all of the information provided, the user may choose one or more output devices to take the print request or print job. On the other hand, the user may choose to decline the output service offered, and choose not to output the document or content to any of those devices. In this case, alternatives may be provided to the user as previously described with reference to step  508  ( FIG. 508 ). 
     Authentication step  604  is optional, but may be necessary if, for example, the use of an output device  140  is restricted to a group of users. In this case, the user may have to provide authentication information to identify him/herself as part of the authorized group to use the service. Examples of authentication methods may include a user&#39;s name, password, personal identification number (PIN), ID number, signatures, security keys (physical or digital), biometric, fingerprint, voice, etc. ID number or IP address of the information apparatus  100  may also be used as authentication information. Such authentication information may be provided by the user manually or detected automatically by the output controller  120  or output device  140 . 
     It should be recognized that  FIG. 6  only provides one embodiment of the service negotiation process  514  of present invention. A service negotiation process  514  having fewer or additional steps may also be possible. As an example, step  604  (authentication) may not be necessary if the use of an output device  140  is not restricted. As another example, one or more steps, such as credit verification, payment, deposit, escrow, and receipt processing may be added to the negotiation process  514  if a service charge is involved. All these and other possible variations, however, shall not depart from the spirit and scope of present invention. 
       FIG. 7  illustrates different processing procedures that may be implemented as part of output or print job processing step  518 . For this description, output device  140  is referred to as a printer and output data is referred to as print data. It should be understood that a printer is only one embodiment of an output device. Display, projection and audio devices are also output devices within the scope of present invention. In no way should the use of printer, in place of output device, and print data, in place of output data, be viewed as restricting the scope to a printing device in the following discussion. 
     In step  700 , output manager  308  processes an input digital document or content  701  and converts it to print data  703  that can be transmitted to output controller  120 , combined controller ( 120 C,  120 F) or directly to printer engine  908 . Rasterization, interpretation, encoding, decoding, etc. may take place in this step. In one implementation, print data  703  may utilize an intermediate format or language to facilitate the transmission of the digital document or content  701  to the output controller  120 . This intermediate format or language may be a predefined input format or language that the output controller  120  can understand. It is also possible in this step  700  that the output manager  308  simply passes the digital document  701  in its original format to the output controller  120  with little processing. In still another exemplary implementation, the output manager  308  may process (e.g. raster image process) the digital content or document  701  into a final print data or output data format compatible to the input requirements of the output device  140 . Encryption techniques may be used to assure the security of communication between information apparatus  100  and output devices  140 . 
     As indicated above, output data or print data (in case of a printer)  703  generated by step  700  may be in various formats. In one embodiment, the print data  703  may be in a final format suitable for sending directly to the printer engine. In this case, the output controller  120  does little or no processing. One exemplary use of this configuration can be implemented in a low cost inkjet printer that does not have a printer controller. In this example, the print data  703  may be in a compressed 1 bit or more CMYK data format that can be sent directly to the printer engine  908  for final output as shown in step  702 . Or print data  703  can be sent to the output controller  120  for possible optional features such as buffering, queuing, and print job management as shown in step  704 . 
     In another embodiment, output manager  308  may generate print data  703  in an intermediate format, language, or instruction that requires further processing. Examples of such format, language or instruction may include, without limitations, Page description languages (e.g. PostScript, PCL), metafiles (e.g. EMF), markup languages (e.g. XML, HTML), image or graphics formats (TIFF, GIF, PNG, JPEG compressed), among others. The intermediate format may also include proprietary solutions in page description languages, markup languages, metafiles, image and graphics formats, encoding and decoding, compression and decompression. The above-mentioned intermediate formats may be used independently, or in combinations. 
     As described above with reference to  FIG. 4 , output controller  120  may be implemented in a variety of ways. Different implementations of output controller  120  may impact the processing procedures described here with reference to  FIG. 7 . 
     As shown in step  702 , the print data  703  is sent directly to the printer or display engine  908  for final output with little or no further processing from output controller  120  or a printer controller  910 . In this case, the print data or output data  703  is preferably to be in a final format or language that can be understood by the printer or display engine  908  that is part of the selected output devices or devices  140 . 
     Alternatively, as shown in step  704 , print data  703  is sent to an output controller  120  connected to or installed within a selected printer or output device  140 . In one embodiment, the print data  703  may be in a final format or language that can be understood and processed by the printer or display engine  908 . In this case, the output controller may buffer the input print data  703  before passing it to the printer or display engine  908  with little or no further processing. In another embodiment, print data  703  maybe in an intermediate format or language not understood by the printer  900  or output engine  908 . Therefore, the output controller  120  may process the print data and convert it into a final format, language or instruction that can be sent to the printer engine (or other output engine, in the case of other type of output device). 
     Regardless of the format of input print data  703 , the output controller  120  may perform additional management functions such as payment processing, service verification, authentication, print job management, queuing, spooling, quality of service among others. 
     As illustrated in step  706  and  708 , the print data  703  may be processed by both output controller  120  (in step  706 ) and printer controller  910  (in step  708 ) separately before being sent to the printer engine  908  for final output. For example, some printers, such as high-speed laser printers, already include a printer controller  910  that has the capability of processing certain types of input such as PostScript, PCL, and XML, among others. In this case, the output controller  120  may process or convert the print data  703  into the input  707  required by the printer controller  910 . Alternatively, in a different implementation, if the print data  703  is already in one of the formats or languages that are compatible and can be understood by the printer controller  910 , the output controller  120  may simply buffer the print data  703  and sent it directly to the printer controller  910  as needed with little or no processing. In step  708 , the printer controller  910  may perform functions such as interpretation, decoding, and raster image processing operations on the input print data  707  (such as a page description language) if such operations were not already performed by output controller  120  or by output manager  308 . The processed result of the printer controller  910  may be sent to the printer engine  908  for final output. 
     As illustrated in step  710 , a single combined controller  120 F,  120 C (as illustrated in  FIGS. 4C and 4F ) that combines the functionalities of output controller  120  and a printer controller  910  may process the print data. Applications that provide feature sets for each controller may share the same resources, such as processor, memory space, storage unit, etc. Under this configuration, the combined controller ( 120 C,  120 F) may further process the print data  703  in step  710  if the print data  703  is not already in the format or language required by printer engine. The combined controller ( 120 C,  120 F) may need to perform interpretation, decoding and rasterization operations in addition to converting the input print data  703  (in one or more of intermediate formats described previously) to the required format, language or instruction of the printer engine  908  for output. If the print data  703  is already in the final format, language or instruction understood by the printer engine  908 , the combined controller ( 120 C,  120 F) might simply buffer the print data  703  and send it as needed to the printer engine  908  for output. 
     Similarly, other than processing print data, the output controller  120  and the combined controller ( 120 C,  120 F) may perform functions such as payment processing (if service charge applies); print job management, queuing, spooling, etc. 
       FIGS. 8A-8E  show a series of exemplary graphical user interfaces (GUIs) rendered at different times on a display screen  800  of an information apparatus  100  to illustrate one implementation of the output process  501  described with reference to  FIG. 5 . The user interfaces shown can be implemented in an information apparatus  100  with or without an operating system. The user interfaces illustrated here are only one example, and other user interfaces may also be implemented within the scope of the present invention. 
     Referring to  FIG. 8A , a user receives an email on an information apparatus  100  using an email application. Functions available to the user are displayed at the bottom of the screen  800 . Printing is one of the functions displayed by the “print” function control or icon  802 . The user may invoke such functions by selecting the icons displayed. The user can make the selection by using, for example, any one or combination of a keyboard, keypad, mouse, stylus, soft keys, push buttons, software command, touch sensitive screen, etc. The user may also make such selection by, for example, a pull down menu, voice-activated command, etc. 
     As the user selects “Print” function control  802 , the output process described with reference to  FIG. 5  is invoked. As a result, the user is notified of all the printers, if any, available that can take the print or output job. If no available printers are detected, the user may also be notified and provided with alternatives as described with reference to steps  506  and  508  of  FIG. 5 . 
     Assume in this example that three printers are found available as the result of discovery process step  502 . In  FIG. 8B , screen  810  informs the user of the make and model of each available printer. The user may obtain further information on each available printer by, for example, selecting a “more information” control or arrow sign  814  displayed after the name of each printer. Further information provided here may include, without limitation, service options offered by each printer, quality of services provided, service charge if any, acceptable payment method, and whether the use of such printer is restricted to a certain group. 
     If a printer is restricted to be used by a certain group, the user may be required to provide identification information before being able to select this printer. For example, to use a printer placed in the hallway of a company office building, a user may have to identify himself or herself as an employee of such company. Password, personal identification number or I.D. number of the information apparatus  100  may be required for authorization purposes. The identification information may be provided by the user manually or detected by the output controller  120  or output device  140  automatically. If the printer provides fee-based service, certain payment process steps may be required additionally, which are not shown in the figures for simplicity. 
     After the user has successfully selected the desired output device or devices in the service negotiation process  514 , the information apparatus  100  may communicate with output controller  120  to identify data or software components, if any, which need to be uploaded to the information apparatus  100  to enable printing. The output manager  308  residing in the information apparatus  100  may participate in, coordinate and manage the communications between applications in the information apparatus  100  and the output controller  120 . 
     In this particular example, as illustrated in  FIG. 8C , the communication between the information apparatus  100  and the output controller  120  has identified that a printer driver needs to be uploaded as displayed on screen  820 . Options are provided to the user as whether or not to continue the process. This information and selection are optional as the process may be implemented transparently to the user. Other optional information that the information apparatus  100  may provide to the user includes, for example, the estimation of time needed for the uploading. 
     The above description gives an example of a printer driver component that may need to be uploaded. Other components and combinations may also be possible; this may include for example a partial print driver, data, software components, or a user interface. A partial print driver or component may for example include only device dependent software components and data specific to an output device. Device independent code and data of the device driver may have been previously installed in the information apparatus  100  and therefore need not be uploaded. It is also possible that no components need to be uploaded because all the components needed for printing to the selected output device  140  may already reside in the information apparatus  100 . Assuming in this example that the user agrees to upload the driver,  FIG. 8D  illustrates an example of an interface when synchronization process  516  proceeds. 
     When the synchronization process  516  is completed, screen  840  is displayed to the user as shown in  FIG. 8E . The user may use screen  840  to select a preference such as page range, number of copies, number of cards per page, color or grayscale, page layout parameters, etc. Selecting “property” control or button  842 , the user may be provided with more device-dependent options such as color and tone adjustments, halftoning parameters, duplexing, resolution, watermarking, etc. 
     Steps  518  and  520  can proceed after the user finishes selecting any preferences. The user, after selecting the confirmation control or “OK” button  844  shown in  FIG. 8E , waits to obtain the printout or other output from the printer or printers  140  selected.  FIG. 8F  illustrates an interface for the printing process of steps  518  and  520 . 
     After the print job has been successfully finished, the user may be provided with an option to keep or delete the printer driver or software components or synchronized device dependent data, which was uploaded to information apparatus  100  in the earlier steps. This option may be beneficial to those mobile information apparatuses  100  with limited memory space or a casual user of that particular output device  140 . A user who frequently uses a selected printer may wish to keep the printer driver, software components, or data installed so that synchronization for uploading components may be skipped when the printer is used again. 
       FIGS. 8A-8E  illustrate only one example of the output process shown in  FIG. 5 . While the above descriptions contain much specificity, these should not be construed as limitations on the scope of the invention, but rather as exemplary embodiment thereof. Other user interfaces and embodiments may also be implemented. The process may also be implemented with more or fewer steps. As an example, security verification, authentication, and payment processing may be added to steps illustrated in  FIGS. 8A-8E . As another example, the step illustrated by  FIG. 8C  may be skipped as the loading process proceeds automatically when the user selects a desired printer or printers. These and other possible variations do not however depart from the scope of present invention. 
     Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents. 
     Having described and illustrated the principles of our invention with reference to an illustrated embodiment, it will be recognized that the illustrated embodiment can be modified in arrangement and detail without departing from such principles. In view of the many possible embodiments to which the principles of our invention may be applied, it should be recognized that the detailed embodiments are illustrative only and should not be taken as limiting the scope of our invention. Rather, I claim as my invention all such embodiments as may come within the scope and spirit of the following claims and equivalents thereto.