Abstract:
A curing lamp apparatus is used for providing electronic voice information to report a number of operating conditions associated with the curing lamp. The apparatus includes a light sensor for sensing output power, voltage and current sensors for sensing input power, a microcontroller for providing a digital number in response to receiving signals from one or more sensors, a programmed voice circuit for retrieving a voice message signal from a memory, address associated with the digital number, and a transducer for receiving and audibly reproducing the voice message signal.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   The present application claims priority under 35 U.S.C. § 119(e) from U.S. Ser. No. 60/329,956, filed on Oct. 17, 2001. U.S. Ser. No. 60/329,956 was filed by at an inventor common to the present application, and is hereby incorporated by reference. 

   FIELD OF THE INVENTION 
   This invention relates to an apparatus and method for providing electronic voice information associated with an instrument, and more particularly, to an apparatus and method for providing electronic voice information associated with the performance and status of a dental curing instrument. 
   BACKGROUND 
   Light curing is a known technique in dentistry for curing, for example, composites and adhesives for the filling of root canals or fissures. Light cure restoratives are utilized throughout the dental care industry from dental maintenance to root canal restorations. Activation and polymerization of light cure restoratives must be carefully controlled. However, a means to inform a dental practitioner of an instrumentation measurement using a clear, audible language or tones appears to be lacking in the prior art. 
   Audible signals are known to be used in association with data items as displayed visually in a dental instrument, as in U.S. Pat. No. 4,968,252 to Creps. Yet, this present approach can lead a dental practitioner to confusion when surrounded by a multitude of such signals each prompting the practitioner for visual monitoring of the display in response to the audio signals. To view the display, the practitioner is thereby required to remove his or her vision from a field of action, resulting in a loss of time and focus on the dental task at hand. 
   Timing is a critical aspect of light curing in dental restorations. For dental fillings, a light cure restorative is typically placed in the apex of a tooth and activated with light. For root canal procedures, after a root canal is sealed, the remainder of the root canal is filled with light cure restorative and activated by light. An undesirable property of light-cured composite resin restorative materials is contraction during the curing process. For proper curing, curing light intensity must be carefully maintained, necessitating accurate tracking and monitoring. Dentists have learned through experience how to minimize the effects of contraction, and how to avoid open margins. Applying and curing small increments of the restorative material and accurate timing have been keys to minimizing these problems. However, managing accurate timing while practicing a dental procedure continues to present a substantial burden for dental practitioners. 
   SUMMARY OF THE INVENTION 
   These and other problems have been in a novel method and apparatus for operating a dental curing instrument. In a first embodiment of the present invention, the apparatus comprises a light sensor for sensing light output power density from a lamp of a curing light, a microcontroller, a programmed voice circuit and a speaker/transducer. The microcontroller comprises a plurality of analog to digital converters each for receiving an analog signal from one of the light sensor and the lamp for conversion to a digital number, a stored program and a memory for analyzing each digital number to produce an associated digital address, and an output for outputting the digital address. The programmed voice circuit, comprising a memory for storing voice messages and a processor for receiving a digital address output by the microcontroller, retrieves a voice message from a memory location identified by the digital number and outputs the voice message for reproduction by the speaker/transducer. 
   In accordance with a first method prescribed by the present invention, the apparatus of the first embodiment is operative to measure an output power density for the curing lamp and to play an audible voice message when the measured output power density exceeds a predetermined threshold. When the measured output density falls below the predetermined threshold, the apparatus of the first embodiment is operative to determine an input power being supplied to the curing lamp, and when the input power falls below a second predetermined threshold, to play an audible voice message indicating that the curing lamp should be replaced. The apparatus of the first embodiment is also operative to count a time of operation while the lamp is active, to store information indicative of a cumulative time of operation for the lamp, and to play an audible voice message announcing that an output power density for the lamp should be evaluated when the cumulative operating time reaches a third predetermined threshold. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     Further particular features of the invention will appear in the description, which will follow, of an embodiment taken by way of example and represented in the accompanying drawing, in which 
       FIG. 1  provides a schematic diagram of a first embodiment of the present invention; and 
       FIGS. 2A and 2B  provide a process flow diagram for illustrating operation of the first embodiment. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A dental curing instrument is disclosed which has the functionality to verbalize the elapsed time of instrument usage as a curing lamp via electronically generated human speech in a chosen language output. For example, during the operation of the disclosed curing lamp, a user may need to know an amount of time that has elapsed. A known method of indicating time elapsed is an electronically generated beep (for example, every 10 seconds). However, such audible beeps can cause some confusion as to the nature of information being related and may distract a user of a curing apparatus from concentrating on the process of curing and caring for the needs of the patient. To solve this problem, elapsed time status is tracked by the disclosed invention and reported in an audible form immediately, allowing the user to focus his or her attention on the dental procedure. 
   The disclosed invention defines an electronic voice apparatus  1  comprising a programmed voice integrated circuit (IC) working together with a microcontroller that offers the user a measurement of the elapsed operating time beginning from the lamp&#39;s initial activation. Instead of using audible beeps, apparatus  1  offers the feature of electronically verbalizing the elapsed time in groups of seconds—“Ten seconds, Twenty seconds, . . . etc.”, for example. 
   Advantageously, apparatus  1  can generate an electronic verbalization of required data in various languages selectable by the user. For example, at NYU Dental Center, dental students are present from all parts of the globe: Russia, India, Asia, the U.S., Pakistan, Israel, and so on. Thus, apparatus  1  offers the functionality to generate and electronically vocalize elapsed time and other information in various languages, from a novel customizable program choice of language selections, which can be utilized to treat dental care needs transcending language barriers by simply selecting a preferred language output. Thus, for example, the instrumentation can be shared by a multitude of students, with each able to easily select a language program choice. 
     FIG. 1  and  FIGS. 2A ,  2 B respectively illustrate apparatus  1  and operating method  400  for the present invention. To begin operation, as illustrated in  FIG. 1 , a lamp  40  is aimed so that light rays  230  impinge on light sensor  240 . Lamp  40  is subjected to an output voltage  30  produced, for example, by a conventional power supply  20  fed by commercial voltage source  10 . 
   Power supply  20 , for example, may be switched on to provide output voltage  30  via a signal supplied by a control output  100  from outputs  90  at Input/Output Port  95  of microcontroller  70 . Microcontroller  70  may be switched on, for example, by closing a trigger switch  215  to connect an input  210  to a system ground  220 . Microcontroller  70  senses, for example, a voltage  65  produced by the light sensor  240  at an analog to digital converter (A/D 1)  64  in A/D section  60 . 
   Operating method  400  begins at starting step  4000  as shown in  FIG. 2A . Operating method  400  may be implemented, for example, by stored programs executed by microcontroller  70  and programmed voice IC  140  of  FIG. 1 . At step  4100  of  FIG. 2A , microcontroller  70  determines whether a signal is being received at A/D section  60 . At step  4200 , a light output power density is determined, for example, based on the voltage  65  produced by light sensor  240 . 
   If light output is not greater than 200 mW/cm 2  at step  4200 , then a curing mode  4300  is executed by the microcontroller  70 . A current  55  is detected at step  4310  via current sensing inputs  45 ,  46  at Analog/Digital Converter 2 (A/D 2)  62  of apparatus  1  as shown in  FIG. 1 . A voltage  50  is detected at step  4320  from voltage sensing inputs  47 ,  48  by the Analog/Digital Converter 3 (A/D 3)  61  of the programmed Microcontroller  70 . Unit power is calculated as a product of current and voltage at step  4330 . At step  4340 , a decision is executed by the analysis routine  4350  to determine whether power is sufficient. If power is insufficient, then microcontroller  70  sets an address  110  associated with the voice message: “Replace the lamp” at step  4355 , and runs an Electronic Speech output routine  4410  to cause address  110  to be output from outputs  90  of microcontroller  70  to an address input  120  of IC  140 , and a run message signal  160  to be provided from outputs  90  of microcontroller  70  to run port  170  of IC  140 . In response to outputs  90 , IC  140  provides an analog output  130  to speaker/transducer  150  for vocalizing the voice message. 
   Returning to step  4200  of  FIG. 2A , if the light output measurement of the unit is greater than 200 mW/cm 2 , then Light Measurement Routine  4400  is initiated by the microcontroller  70 . At step  4405 , an analog signal is received from the Light sensor  240  via A/D controller  64  and converted into 4 digits of binary coded decimal (BCD) numbers. These numbers are used to represent the decimal digits 0–9. BCD code uses 4-bit binary coding at each decimal digit. To convert a BCD number into decimal, every 4-bits is converted into a decimal number. To convert a decimal number into BCD, each digit is simply converted into a 4-bit binary number, and is forwarded to a display (for example, a LED or digital read-out) providing digits for thousands, hundreds, tens and units as illustrated by positions  4422 ,  4424 ,  4426  and  4428  at step  4420 . 
   At step  4430 , if the decimal for thousands  4422  is greater than 0, an address is then set relative to thousands at step  4440 . Electronic Embedded Speech routine  4410  is run, running electronic verbalization of the thousands measurement for the unit instrument at steps  4440 ,  4450  by microcontroller  70  communicating an appropriate address signal to the programmed voice IC  140  so that an associated voice message may be audibly reproduced by a speaker/transducer  150 . 
   When the verbalizing of thousands measurement speech loop is complete at step  4460 , the address statement is then set, relative to hundreds at steps  4470 ,  4480  as shown in  FIGS. 2A ,  2 B. After the associated voice message is output by IC  140 , IC  140  sends a message complete signal  190  from message port  180  to an input port  200  at Input/Output Port  95  of microcontroller  70 . Speech routine  4410  is again run, running verbalizing of the hundreds data by the means previously described with reference to verbalizing thousands data. 
   When it is determined that the electronic verbalizing of hundreds speech loop is completed at step  4490 , microcontroller  70  sets the address for the statement relative to the tens at steps  4500 ,  4510  and runs speech routine  4410 . When the message is completely communicated at step  4420 , then microcontoller  70  sets the address for the statement at step  4435 , relative to the units of the data measurement provided by apparatus  1 . A speech routine  4410  electronically verbalizes the units measurement at step  4425  from microcontroller  70  by signaling programmed voice IC  140 , which outputs a voice signal to the speaker/transducer  150 . When the output to speaker/transducer  150  is completed, operating method  400  returns to step  4100  of  FIG. 2A . 
   An active lamp timer (not shown) is implemented by microcontroller  70 , which supervises the real working time of the unit. The length of time the lamp is active is stored in a memory within the microcontroller  70 . The counted time maybe conveniently stored into a memory of microcontroller  70 , and is not erased, for example, when unit&#39;s electrical power is turned off. This feature helps to log real lamp usage, and can be configured to provide a schedule maintenance alert message for a user. 
   Over a lamp&#39;s lifetime, its light intensity decreases slowly, little by little. Most curing lamp instruments contain a powerful lamp, a spectrum filter, and a fiber optic tip, all of which are critically aligned. Any misalignment results in poor instrument operation. For this reason, it is very important to check the light intensity periodically to prevent insufficient curing. The disclosed invention provides this feature, such that the total amount of time that the lamp is used is stored in the memory of microcontroller  70 . Apparatus  1  may accordingly notify the user by electronic “human” speech when it is time to check the lamp&#39;s intensity. This significantly lessens the burdening step of having to check instrument status. 
   Filament evaporation for lamp  40  of  FIG. 1  causes the light output of lamp  40  to decrease over time. As a result, the filament&#39;s resistance increases, the current decreases, and the power lowers respectively. Light intensity decreases as power decreases. The present invention allows a user to continuously monitor the power applied to the lamp  40 . Every lamp&#39;s resistance is unique. Therefore, even though a regulated voltage may be applied, power will be different with each individual lamp  40 . The present invention allows a user to measure the power when a lamp has been installed or replaced, and store this value in the memory of miocrocontroller  70 . 
   Returning to  FIG. 2A , to aid a user at each lamp activation of apparatus  1 , a power measurement is initiated within curing process  4300 . At step  4340 , the measured power is compared with a stored ID value representing an initial value for lamp  40 . If the measured power is out of a specified range, determined by the microcontroller  70  with reference to the initial ID value, an electronically generated voice message  4415  is made to “Replace the lamp” as indicated at steps  4355 ,  4410 . Uniquely, apparatus  1  of  FIG. 1  features functionality such that the light intensity never needs to be measured by a human operator to determine a replacement time for the lamp. Rather, apparatus  1  constantly monitors the lamp, and suggests replacement at an appropriate time for the ease and convenience of the user. 
   A lamp utilized in the present embodiment of apparatus  1  is a halogen-based lamp. Other lamp types which can be configured alone or in combination to produce like power densities are fully contemplated within scope of the present invention. 
   Returning to step  4340  of  FIG. 2A , if the Power is determined to be sufficient at step  4350 , then a decision is made at step  4360  to determine “Is the elapsed time exactly 10, 20, 30, 40, 50 or 60 sec?”. If yes, then apparatus  1  steps to set an address relative to the elapsed time at step  4362 , executes speech routine  4410 , and electronically verbalizes the elapse time at step  4364 . At step  4368 , apparatus  1  determines “Is the elapsed time 60 sec?”. If yes, then the routine of the unit ends at step  4380 . If no, a check is made to determine whether apparatus  1  has been stopped by a user at step  4370 . If yes, then method  400  ends at step  4380  of  FIG. 2B . Otherwise, method  400  returns to step  4100  of  FIG. 2A . 
   A display unit (not shown) may be optionally included in the dental curing instrument itself or on an adjacent control panel as an additional means for indicating data. The display unit may comprise segmental, LCD, LED or any other display means, and may be driven, for example, by the digital numbers provided by A/D section  60 . 
   The foregoing describes the invention in terms of embodiments foreseen by the inventor for which an enabling description was available, notwithstanding that insubstantial modifications of the invention, not presently foreseen, may nonetheless equivalents thereto.