Abstract:
The present invention includes an automatic commodity or services billing and metering system that when installed does not damage any existing meters or gauges, will fit virtually all known meters and gauges, and has incorporated into the system programmable reading ability to allow reading and accumulation of data by unit, hourly, daily, weekly, monthly or any other form of counting required by the customer. The meters are read by various means, one method is by counting and or sensing radiation increases and decreases of radiation emitting from a meter hand or gauge passing a sensor to generate a count. The read data is then sent via the Internet through the telephone line, by satellite, or by cellular phone connection to an offsite central billing and payment processing center where the rate payer and the utility or customer will have various forms of programmable access to its consumption data.

Description:
BACKGROUND OF THE INVENTION 
   1. Technical Field 
   The present invention generally relates to meter reading systems. More particularly, the invention relates to an automated approach to meter reading, billing and payment processing that reduces retrofitting costs, increases functionality and enhances performance. 
   2. Discussion 
   In the utility industry, recent difficulties associated with deregulation have placed a premium on cost reduction and automation. In particular, the complexity of conventional billing processes has placed meter reading approaches and systems under heightened scrutiny. In fact, the majority of utility companies still rely upon a manual meter reading approach that involves a significant labor cost, invoicing delay and equipment costs. While some companies have opted to reduce the frequency of meter reading and estimate commodity usage during interim periods, such an approach lends itself to uncertainty and adds risk to the overall operation. 
   While a number of approaches to automating the meter reading process have been made, certain difficulties remain. For example, most conventional automation approaches require meter replacement or a complex retrofitting process. With the hundreds of millions of meters currently in service, it is easy to understand that the associated costs make these approaches impractical in a modern economy. It is therefore desirable to provide a method and system that streamline the billing process while at the same time reduce operating costs and enhance performance. 
   SUMMARY OF THE INVENTION 
   The Electronic Meter Reader System of one embodiment of the present invention includes an automatic commodity or services billing and metering system that, when installed does not damage any existing meters or gauges, will fit virtually all known meters and gauges, and has incorporated into the system programmable reading ability to allow reading and accumulation of data by metered unit, hourly, daily, weekly, monthly or any other form of counting required by the customer. 
   The meters equipped with the reader system may be read by various means. For example, one method is by counting and or sensing radiation increases and decreases of radiation emitting from a hand or gauge passing a sensor to generate a count. Another system to read meters or gauges is the use of an interface to receive the data from LED or LCD displays. The third system in reading meters or gauges is the CMOS reader that sends an image to a computer like a fax is transmitted, for subsequent deciphering of the image to numbers or counts. 
   The system of one embodiment of the present invention is a significant improvement over traditional magnetic reading systems because the radiation element in the embodiment can be sensed through metal, glass and plastic, and is always accurate regardless of environmental variances. More importantly, the system is significantly more difficult to tamper with, as a user cannot simply add a neodymium magnet to the surface to destroy the reading ability, as is commonly done in magnetic reading or inductive reading devices. 
   The meter read process device of one embodiment of the present invention is part of the billing and meter process system, and is located within a radio frequency transmission distance of the meter reader. The meter reader communicates directly with the process device and provides the data required to be sent to the billing system by telephone or satellite. 
   A digital transceiver operating in accordance with a commercially available protocol such as CDMA, TDMA, etc., is included in both the process and meter reading device, and provides for the exchange of information via a wireless data communication channel. As is well know in the prior art, the CDMA communication technology provides for thousands of frequencies to be used in varying amplification between 46 MHz. to 2.7 Ghz, and may be encrypted thereby providing absolute security for reading and processing information. 
   One of the most important elements of the billing and meter reader system of the present invention is the Internet access billing and payment collection system. Located at a remote location, thousands of miles away, is a high speed billing computer system and Internet server that gathers information from millions of customers. The billing system allows the rate payer and utilities or commodity owners to have access to various data effecting their accounts. 
   The information available for the rate payer is use, billing and payment history and the rate payer has the ability to authorize payment, via the Internet, to pay for services rendered and or commodities purchased. The rate payer need only send information to the billing system to authorized payment, such as a bank account or credit card, to allow the billing system to debit the rate payers bank account or charge a credit card. If the rate payer elects to use the Internet payment system, the rate payer and the utility or commodity owner will share in the savings from not using the postal system. Further, the billing system allows the utility or commodity owner to gain access to its account information such as, total collected by hour, day or month and to access various preprogrammed quantity information schedules such as product draw per line or spread sheets for payment and sales history. 
   An important improvement in the present invention is the ability of the system to stand on its own as a complete reading, billing and collection systems whereby, once the system is installed, there is no need for the utility or commodity supplier to drive by or inspect the meter reading system, or to take data by rolling data collection trucks. Furthermore, the customer has the additional advantage of being able to pay for all metered services and products on-line, via the Internet. The commodity suppliers and utility companies need not own and operate billing and collection centers, the system is all inclusive under a “stand alone” real time approach, and the system is user friendly. The system has programmable variables that can be installed in the reader, process system and billing and collection system. These programmable features allow the company to program trouble codes into the system to identify faults that may be transmitted from the meter reader during the ordinary retrieval of consumption information. 
   It is to be understood that both the foregoing general description and the following detailed description are merely exemplary of the invention, and are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed. The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute part of this specification. The drawings illustrate various features and embodiments of the invention, and together with the description serve to explain the principles and operation of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The nature, objects, and advantages of the present invention will become more apparent to those skilled in the art after considering the following detailed description in connection with the accompanying drawings, in which like reference numerals designate like parts throughout, and wherein: 
       FIG. 1  is a schematic representation of the system of the present invention, showing multiple meter reading devices, a communication hub, and a central billing station; 
       FIG. 2  is a typical electrical panel having an electric meter equipped with the meter reading device of one embodiment of the present invention; 
       FIG. 3  is a detail view of a portion of the electric meter shown in  FIG. 2 , showing the placement of the radioactive resin and the location of the sensor head on the external surface of the electric meter; 
       FIG. 4  is a graphical representation of the signal generated by the sensor head depicting two separate meter readings, showing differing periods, and having differing amplitude signals; 
       FIG. 5  is a block diagram representing the circuitry of a meter reading device of the present invention, including signal conditioning circuitry, a microprocessor, a transmitter/receiver, and a memory; 
       FIG. 6  is a typical water meter equipped with the meter reading device of one embodiment of the present invention; 
       FIG. 7  is a typical gas meter equipped with the meter reading device of one embodiment of the present invention; 
       FIG. 8  is a typical gauge equipped with the meter reading device of one embodiment of the present invention; 
       FIG. 9  is a diagrammatic representation of the meter reading device used in conjunction with the meter equipped with an RS232 or equivalent data port for receiving the consumption data from the meter directly; 
       FIG. 10  is a front view of an example of a dial in accordance with an alternative embodiment of the present invention; 
       FIG. 11  is a sectional view of the dial shown in  FIG. 10  taken along lines  11 - 11 ; 
       FIG. 12  is a front view of an example of a decade meter in accordance with an alternative embodiment of the present invention; and 
       FIG. 13  is a sectional view of the decade meter shown in  FIG. 12  taken along lines  13 - 13 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention has the capability to provide billing services to the rate payer, or customer, and the utility, or commodity supply companies, that have never been provided in the past. These services include the ability of all the parties to have interactive access to their respective account information and arrange payment or obtain use information on-line, using the Internet. 
   The present invention also provides the commodity supplier or utility companies with the ability to access their respective customer accounts in a variety of programmed formulas that provide data in multiple use summaries to monitor current use, plan for future infrastructure expansion and add and subtract customers as business warrants. Also, the ability to instantaneously determine the current commodity consumption throughout service areas, regions, or even specific distribution channels, such as electrical grids, provides the commodity supplier with the information necessary to ensure the highest quality of service. Moreover, the instantaneous measurement of the consumption, and the ability to analyze by time period the prior consumption rates, provides information useful to commodity supplier for future development, expansion, or upgrading its distribution systems. 
   Because all commodity suppliers can use the system of the present invention, the billing system can invoice a customer for all utilities on single invoice, and thus saves postage and mailing cost associated with billing and receiving payments from multiple commodity suppliers, as is the conventional manner today. These cost savings can be passed on to the consumer and the supplier. Since there are billions of meters that require billing and reading each day, week or month, the savings to customer and suppliers can be enormous if such a system is offered. 
   The read system has the ability to read actual use of commodities such as water, gas, crude oil, chemicals, or electrical energy by unit, hour, day and or month, as so programmed at the request of the utility, supplier, rate payer or customer. The meter reader may use any of three distinct reading approaches. One approach involves the use of a radioactive sensor that reads a meter hand as the hand rotates around a conventional meter or moves on a meter scale or dial. Another approach involves reading information from a numeric display, using CMOS visual reading that is sent to a computer for analysis. The display information can be processed at an off site computer, which deciphers the image to numbers. The last method involves reading LED or LCD display numbers by connecting the output of the display to a sending unit. 
   The overall system has a process system that receives data transmitted in various ways from the read system. Transmission of data can be sent via hardwire connection or by radio transmission. The reader will send to the processor the serial number of the meter, or other customer information, and the read or reads presently obtained from the meter. The process system accumulates real time information or passive information from the reader, as the customer so programs the reader, and the process system then sends the data directly to the billing computer, via the Internet. The process system has the ability to accept reads from many different types of readers at different times of the day and night and stores the information in its memory for future transmission through the Internet to the billing and collecting computer. 
   One embodiment involves the development and installation of a drop of premixed liquid resin, or adhesive, containing a radioactive material or compound that emits radiation at given rates over time after placement upon a meter or dial. Once the resin or adhesive is placed, the resin or adhesive dries hard and adheres to the meter hand, dial or tumbler. 
   A radioactive detection sensor detects the rise and fall of the radioactive emissions radiating from the radioactive substance within the meter as the hand or dial passes the detection sensor. In a preferred embodiment, this radioactive compound or material has a half-life of several decades in order to minimize the replacement and repair costs for meter reading devices in the present invention. It should be appreciated, however, that a shorter half-life is also useful and fully contemplated in the present invention. The detection sensor can be placed anywhere on the outside of the meter, and the changes in radioactive emissions received by the sensor will be registered by a counter each time the hand or dial moves past a designated point, without retrofitting the meter. When radioactive detection is used, the radioactive emissions pass directly through metal, glass or plastic without damaging the meter. 
   The invention also provides for the installation of a variable quantity radioactive sensing device that detects an increase or decrease in radioactive emissions in order to read a scale measurement or pressure gauge. This is achieved by placing a radioactive emission reading sensor at an angle to the movement of the meter hand. Once the sensor is placed on an angle to the meter hand, the meter can be read by the variation of radiation received. The number or quantity of emissions is read by offsetting the collecting sensor in various degrees that vary perpendicular to the meter hand, dial, or gauge hand. A computer program can provide data conversion by converting the emission rate to counts, counts over specific time frame, or as required by the customer. 
   A radioactive detection sensor can detect the rise and fall of the radioactive emissions radiating from the meter hand as the hand passes the detection sensor. The detection sensor, can be placed anywhere on the outside of the meter and the changes in radioactive emissions received by the sensor are registered in a counter each time the hand or dial is detected moving around the meter, without retrofitting the meter. 
   A radio frequency (RF) based communication system includes a transmitting signal comprising of an external power source or external solar powered source, a battery back up, and utilizes a digital transmission and receiving technology known in the art to transmit and receive data generated by the meter reader system, within radio transmission distance. The data transmitted from the meter reader may include the actual count data of the meter at the time of transmission, the serial number of the meter and customer information as may be stored in local memory. The receiver receives the counts of the meter by units, hours, days, and or months, stores the count information in its internal memory, and then sends count data to the process system as preprogrammed by the customer. 
   The RF communication system described includes a microprocessor and a digital communication system, such as a modem, and a process system that sends count data collected from the meter reader through the telephone land line, cellular telephone communication channel, satellite communication channel, or the Internet, to a central billing and payment processing computer without the use of a mobile node or movable data collection equipment. Because each meter reader is preferably self-powered, power outages do not effect the system. 
   The metering, communication and billing and collection system of the present invention supports multiple meter readers, attached to virtually any meter or gauge, and counts by units, hours, days, dates and or months, as preprogrammed at the customers choice. 
   The use of an Internet server to obtain data sent from the process system provides for the exchange of information using a standard information protocol, such as TCP/IP. The server may be programmed to obtain and store the meter information required from each reporting meter process system, and then download the information to the billing and collecting computer system upon demand. The server allows the collection of data at a much greater rate than is achievable under conventional meter reading and downloading technologies. 
   The meter reader of the present invention is programmable and shall alert the process system with trouble codes defining events such as, but not limited to, low battery, reporting collected data irregularity, power outages or supply limitations, or other conditions affecting the distribution and consumption of the commodity. 
   The billing and collecting computer may also be programmable to allow the customer, known as the utility or commodity service or product provider, to have access to all collected usage information on their accounts. This information may include, but not be limited to, total consumption by customer, date, hour, day, week, month, year, branch or line of service, cumulative totals of products, or services, delivered in various retrieval forms. The billing and collecting computer shall permit the customer to retrieve financial data, such as payment history per account, date of billing, date of collection, type of payment made, such as on-line check debit, credit card, or check payment, and the system may also provide a variety of combinations of financial information as required by a specific customer. 
   The billing and collecting computer is programmable and allows the rate payer or secondary customer of the prime customer to have access to all collected information on their accounts. This information shall include, but not be limited to, totals by customer of all products and or services by unit, date, hour, day, week, month, year, cumulative totals of products, or services, delivered in various retrievable formats. The billing and collecting computer preferably permits the rate payer to retrieve a variety of financial data, such as payment history for the particular account, date of billing, date of collection, type of payment made, be it online check debit, credit card, or check payment, and the system shall provide a variety of other combinations of financial information as authorized to be released by the prime customer. 
   The rate payer, by using the Internet or by letter, can select his or her electrical or gas supplier if he or she discovers a more economical rate for the commodity being purchased. This is particularly useful in areas recently deregulated as the unit prices of various commodities fluctuate greatly, providing a significant financial incentive to the rate payer to identify and switch to the most inexpensive commodity supplier. 
   Referring now to  FIG. 1 , a schematic representation of the Electronic Meter Reader System (or meter management system) of the present invention is shown and generally designated  100 . Electronic Meter Reader System  100  includes multiple meter reading devices  102  in wireless communication with a communication hub  104 , which communicates usage information to central billing station  106 . 
   Meter reading device  102  includes a meter reader unit  110  and an antenna  112 . Each meter reader unit  110  is more thoroughly described in conjunction with  FIG. 5  below. 
   Communication hub  104  receives a communication signal transmitted from antenna  112  of meter reader  110  via antenna  114 . Once received by antenna  114 , the communication hub computer  116  decodes the usage data from the transmitted signal and stores the usage data. Periodically, the communication hub computer  116  transmits the stored usage data to a central billing station  106 . For instance, communication hub computer  116  may transmit the usage data via a satellite communication transceiver  118 , to satellite  120 , which in turn relays the usage data to satellite transceiver  126  on central billing station  106 . This satellite communication link is particularly useful in installations of the Electronic Meter Reader System  100  where access to traditional wired communication systems such as telephone lines, is not available. 
   Alternatively, communication hub computer  116  may transmit the usage data via a telephone line  122 , either by using a traditional modulator/demodulator (i.e., modem), or via an Internet communication protocol, such as TCP/IP, to the central billing station  124 . It can further be seen that the communication hub computer  116  can transmit the usage data via an antenna  118   a  over a cellular telephone communication link  20  to a billing station antenna  126   a . It should be noted that the communication link  20  includes various base stations and relay stations as necessary to complete the transmission. Once the central billing station  124  has received usage data for each, or a number of meter reading devices  102 , a single invoice  128  is created. The invoice  128  can be either mailed to the consumer or sent to the consumer via the Internet, or the costs for the usage may be automatically debited from the consumer&#39;s financial accounts, as is fully set forth above. 
   Referring now to  FIG. 2 , a typical electrical panel is shown and generally designated  200 . Electrical panel  200  includes an electric meter  202  having one or more dials  204  having a dial arm  206 , and having a metering disc  208  which rotates in accordance with electricity usage through the electrical panel  200 . Electrical panel  200  is also equipped with the meter reading device  102 , including a sensor  146  attached to an exterior wall of the electrical meter  202 . Sensor  146  is in electrical communication with meter reader circuitry  152 , which derives its electrical power, in part, from solar cells  154 . It should be noted that sensor  146  and circuitry  152  may be combined for space and cost saving considerations. Meter reading device  102  is also equipped with antenna  112  shown as a dipole antenna. However, it is to be appreciated that the particular design of the antenna  112  is merely exemplary, and that any other antenna known in the art for use with the frequencies involved is fully contemplated herein. 
   In accordance with the Electronic Meter Reader System of the present invention, dial arm  206  is equipped with a drop of resin containing a radioactive isotope. Alternatively, any moving part of a meter having a movement corresponding to the usage being metered, will suffice for use with the Electronic Meter Reader System of the illustrated embodiment of present invention. For instance, alternatively, a drop of radioactive resin  140 A may be placed on metering disc  208 . Once the radioactive resin is placed on a moving part of electric meter  202 , sensor (or other input device)  146  will sense the relative strength of the tracking signal created by the radioactive material. 
   Unlike the currently available metering systems, the positioning of the radioactive resin is not critical as the reception of radioactive emanations by sensor  146  is significantly less affected by environmental variants, such as moisture, humidity, etc. Furthermore, radioactive emanations pass freely through most materials, even metallic meter covers, such that the Electronic Meter Reader System  100  can be applied to virtually all meters currently in use, including all electric, gas, and water meters. 
   Referring now to  FIG. 3 , a detailed view of a portion of the electric meter  202  is shown, further showing the placement of the radioactive resin  140  on dial arm  208 , and the location of the sensor head  146  on the external surface of the electric meter  202 . Sensor head  146  may be attached to the outer surface of the electric meter using adhesive  148 , or any other means known in the art. As shown, when dial arm  208  rotates in direction  209 , the distance between the radioactive resin  140  and sensor head  146  decreases until a minimum distance  144  is reached. When the radioactive resin  140  on dial arm  208  is a minimum distance  144  from sensor head  146 , the radioactive tracking signal received by sensor head  146  is at a maximum value. As the dial arm  208  continues to rotate, the radioactive signal decreases until a minimum value of radioactive signal is received by the sensor head  146 . 
   Referring to  FIG. 4 , a graphical representation of the signal generated by the sensor head depicting two separate meter readings, showing differing periods, and having differing amplitude signals is shown and generally designated  300 . Graph  300  includes a first plot  302  having a period F 1 , designated  304 , and an amplitude  306 . The amplitude  306  represents a sensor head  146  in close proximity to the radioactive resin  140  at its closest position. Also, period  304  corresponds to a certain speed of rotation of dial arm  140 . 
   In contrast, a second plot  320  is shown on graph  300  and has a first period F 2 A, designated  322 , an amplitude  324 , and a second period F 2 B, designated  326 . As shown, second plot  320  has a smaller amplitude  324  than plot  302 , and represents a sensor head  146  being mounted further away from radioactive resin  140 , or a smaller quantity of strength of the radioactive resin  140 . Also, the period  322  is somewhat shorter than period  304  of plot  302 , signifying a faster rotational speed of dial arm  208 . For illustrative purposes, plot  320 , changes its period during the time interval shown to a second period  326 , which is somewhat shorter than period  322 , corresponding to a still more rapid rotation of the dial arm  208 . The more rapid the rotation of the dial arm  208 , the higher rate of consumption being measured by electric meter  202 , or any other gas, water, or other meter. 
   Based on the rotation of the dial arm  208 , the radioactive signal strength received by sensor head  146  may be analyzed to determine the number of rotations. This determination may be accomplished by integrating the electrical output of the sensor head  146  to determine a maximum value over a short time interval, or by establishing an average signal value, shown by dashed lines  308  and  328 , and determining when the measured radioactive signal strength passes the established average value. Using these methods, the number of rotations of the dial arm  208  may be determined. 
   It should be noted that when a radioactive material is used, the isotope can be selected to provide virtually any half-life desired. For example, Cesium-137 has a half-life of 15 years. It should also be noted that the meter reading device can be readily designed to count rotations well beyond the half-life of the radioactive isotope. In fact, the photodetector, which typically generates a voltage based on the strength of sensed gamma rays, can be connected to a resistor-capacitor (RC) circuit or transistor that is designed to switch in response to decreases in gamma ray strength. Thus, as the radioactive material continues to decay the ability of the meter reading device to count rotations is only limited by the dynamic range of the photodetector. 
   Once the number of rotations of the dial arm  208  is determined, the consumption of the particular meter may be determined. For instance, if a single rotation of dial arm  208  corresponds to one-thousandth of a kilowatt hour, then the power consumption may be determined by counting the number of rotations, and multiplying that by the corresponding multiplier to determine consumption. 
   Referring now to  FIG. 5 , a block diagram representing the circuitry of the meter reading device  102  is shown and includes a meter reading unit  110 , a radioactive sensor head  146 , and a solar cell  154  for receiving solar radiation. Meter reading unit  110  receives an electrical signal  150  from sensor head  146  and amplifies and conditions that signal with amplifier  160  and  162 , respectively. Once conditioned, microprocessor  164  captures the signal corresponding to the dial arm rotation and determines the usage data for that meter, which may be stored in digital memory  166 . 
   Meter reading unit  110  may transmit the usage data via transmitter/receiver  168  and through antenna  112 , as discussed above in conjunction with  FIG. 1 . Power for the operation of the meter reading device  102  may be derived from batteries  172 , solar cells  154 , hardwiring to the electrical service, the telephone system, inductively coupling necessary power from the electrical service, or a combination thereof. The power conditioning unit  170  regulates and manages the supply of power to the unit for transmitting and for storing the usage data. 
   Referring now to  FIG. 6 , a typical water meter is shown and generally designated  230 . Water meter  230  is equipped with the meter reading device of the present invention and includes meter reader circuitry  152  attached to antenna  112 , and in electrical connection with sensor head  146 . Water meter  230  includes an inlet pipe  232  and an outlet pipe  234 . Meter dial  236  includes a dial arm  238  equipped with a radioactive marker  240 , such as the radioactive resin discussed above. Instead of dial  236 , or in addition thereto, water meter  230  may be equipped with a decade rotating readout  242  having a number of decade readout wheels. One of the decade readout wheels, preferably the least significant digit, is also equipped with a radioactive marker. Sensor head  146  is attached to meter casing  237  such that the radioactive signal received by sensor head  146  varies as the position of dial arm  240  or decade wheel  242  changes, thereby providing the metering data necessary for use of the present invention. 
   It should be noted that water meters such as meter  230  are often surrounded by a concrete barrier such as a vault, or are buried under a sidewalk. The barrier therefore typically prevents light from striking the meter reading device. As a result, it is often difficult to deliver solar power to the meter reading device under conventional methods. One embodiment therefore provides a unique method of retrofitting such a meter with a solar cell. An opening is created in the concrete barrier by making a small saw cut, which is typically on the order of three to five square inches. The solar cell can then be electrically connected to the meter reading device such that the solar cell is able to provide power to the meter reading device based on light striking the solar cell. The process also provides for positioning the solar cell in a light-accessible location with regard to the opening. The opening is sealed with a clear, hardening resin such that the resin enables light to strike the solar cell. 
   Referring now to  FIG. 7 , a typical gas meter is shown and designated  250 . Meter  250  includes a display  252  having a bezel  254 , often made of glass, and covering one or more dials  255 , each having a dial arm  256  equipped with a radioactive marker  257 . The sensor head  146  receives the radioactive signal from dial arm  256  and, as it rotates as discussed above, the signal varies to provide the necessary metering information and data for the present invention. 
   Referring now to  FIG. 8 , a typical pressure gauge is shown and generally designated  270 . Gauge  270  includes a gauge arm  272  having a radioactive marker  274  which, depending upon the pressure measured by the gauge, moves in direction  276  to a new position  278 . A sensor head  146  is positioned the outside of gauge  270  to receive the radioactive signal produced by the radioactive marker  274 , thereby determining the position of the gauge arm  272 . Once the gauge is calibrated with the present invention, the relative pressure of the compressed air or other gaseous material can be determined, and thus, the necessary consumption data may be determined. 
   Referring now to  FIG. 9 , a digital meter is shown and generally designated  290 . Meter  290  includes a digital readout  292 , such as a Light Emitting Diode (LED) display, or liquid crystal display (LCD), and a data output port, such as an RS232 data port. The meter reader circuitry  110  of the present invention may be equipped with a cable  296  having a corresponding mating plug  298  for engaging the output port  294  to receive the consumption data from the meter directly. 
   It should be noted that any of the meters described herein can be have a contrast sensing substrate placed over the display, where complementary metal oxide semiconductor (CMOS) sensing technology characterizes visual output from the display of the meter. CMOS imaging devices are described in a number of sources such as U.S. Pat. No. 6,287,886 to Pan. 
   Other Embodiments 
     FIGS. 10-13  demonstrate that the present invention also provides a mechanism for limiting human exposure to emissions from the radioactive isotope. For example,  FIG. 10  shows a meter  300  having a radiation shielding container  304  coupled to a dial  302  of the meter  300 . As best seen in  FIG. 11 , a radioactive isotope  306  is disposed within the radiation shielding container  304 , where the container  304  has surfaces defining an opening  308 . The radioactive emissions  301  exit the container  304  through only the opening  308  and therefore can be provided with more directivity. It will be appreciated that human exposure can be further reduced by closing off the opening  308  until the desired meter retrofit is to be performed. At such time, the retrofit technician can use any acceptable punching or drilling device to create or expose the opening  308 . It will further be appreciated that although the container  304  is illustrated as having a cylindrical geometry, other geometries such as spherical, conical, square cross-section, etc. are possible depending upon the circumstances. The container  304  is made of a radiation-resistant material such as lead. 
   Turning now to  FIGS. 12 and 13 , a radiation shielding container  310  is shown, where the container  310  is coupled to a decade readout wheel  312  of meter  314 . The radioactive isotope  316  directs radioactive emissions  311  through opening  318 , which limits the effective exposure area as discussed above. 
   While there have been shown what are presently considered to be preferred embodiments of the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the scope and spirit of the invention.