Abstract:
The present invention is to provide a cellular phone capable of measuring temperature including a liquid crystal display, a CPU and an IR temperature measurement means coupled to the CPU, wherein a first GPO pin and a second GPO pin of the CPU are adapted to control power supply of a power supply IC and start or stop of the IR temperature measurement means respectively, and in response to receiving a temperature measurement signal, the CPU performs a plurality of processing and conversion steps to show a corresponding temperature on the display.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to cellular phones, and more particularly to a cellular phone capable of measuring temperature by an IR (infrared) means, including a liquid crystal display, a CPU and IR temperature measurement means coupled to the CPU, for performing not only the functions of communication but also the functions of a temperature measurement gun.  
       BACKGROUND OF THE INVENTION  
       [0002]     The world we are living in has entered into a new era with information technology and electronics being progressed rapidly. All kinds of information products and peripherals are invented due to the fast progress in computer science and technology. The fast development of such new products brings much convenience to our daily life. In response to various kinds of consumer electronic products being developed, most users become more critical with respect to the features and/or quality thereof.  
         [0003]     The demand for IR temperature measurement guns and non-contact type IR thermometers has increased steadily before 2003. Further, the demand for such electronic products has risen significantly since the outbreak of SARS (severe acute respiratory syndrome) in 2003.  
         [0004]     Conventionally, most electronic products of the type available on the market have a single feature with disadvantages of being high in the manufacturing cost and not easy to carry. Moreover, people may feel inconvenience by carrying a temperature measurement gun for measuring temperature anyplace anytime.  
         [0005]     Thus, it is desirable to incorporate an IR means in a cellular phone to form a novel cellular phone so as to meet the large demand for such electronic products on the market and thus increase the market share. In other words, the novel cellular phone not only can operate as a typical cellular phone but also can operate as a typical temperature measurement gun. As such, there is no need of carrying an additional temperature measurement gun simply for the purpose of temperature measurement. As an end, the above problem is solved. Moreover, such novel product definitely can contribute much to the sale of cellular phones produced by a cellular phone manufacturer. In addition, the novel product is beneficial to the vast consumer. In view of above, the development and availability of the multifunctional cellular phone are very important to the cellular phone manufacturers.  
         [0006]     Typically, people like to carry a cellular phone. Thus, it is convenient for a person to make or receive a call anywhere anytime. It is envisaged that a minimum modification of hardware and software of a cellular phone can embody the novel cellular phone with a minimum increase of the manufacturing cost. Such not only decreases the financial burden borne on the consumer but also increases the sale of cellular phones.  
         [0007]     It is understood that the sale growth of temperature measurement guns is closely related to the outbreak of SARS. But this does not mean that such electronic products are short-term products. To the contrary, in one aspect SARS has awakened people about the importance of health products. Thus, the market of such electronic products is still good in terms of long period of time.  
       SUMMARY OF THE INVENTION  
       [0008]     A primary object of the present invention is to provide a cellular phone capable of measuring temperature as a typical IR temperature measurement gun in addition to making or receiving a call. The present invention can bring a great convenience to users since people like to carry a cellular phone anywhere. The present invention further provide a cellular phone capable of measuring temperature including a liquid crystal display, a CPU, IR temperature measurement means including a plurality of pins each coupled to a corresponding one of a plurality of pins of the CPU, a power supply IC for supplying power to the IR temperature measurement means, and an IR sensor wherein a first GPO pin and a second GPO pin of the CPU are adapted to control power supply of the power supply IC and start or stop of the IR temperature measurement means respectively, and in response to receiving a temperature measurement signal, the CPU performs a plurality of processing and conversion steps to show a corresponding temperature on the display. By utilizing the present invention, the above drawbacks of the prior art can be overcome. These drawbacks are that most prior IR temperature measurement guns and non-contact type IR thermometers available on the market have a single feature with disadvantages of being high in the manufacturing cost and not easy to carry.  
         [0009]     The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a schematic block diagram of a conventional IR temperature measurement device;  
         [0011]      FIG. 2  is a schematic block diagram of a cellular phone incorporating the IR temperature measurement device in  FIG. 1  thereinto to form a cellular phone of the invention;  
         [0012]      FIG. 3  is a top view of the cellular phone in  FIG. 2 ; and  
         [0013]      FIG. 4  depicts an exemplary data format according to the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]     The invention is directed to a cellular phone capable of measuring temperature by an IR (infrared) means. Currently, there is a type of much compact IR temperature measurement device available on the market as a result of the fast progress of semiconductor based sensor technology. The IR temperature measurement device comprises an IR sensing probe and a specially designed signal processing circuit. Thus, the IR temperature measurement device has advantages of being simple in use, inexpensive, and high in reliability and accuracy.  
         [0015]     In view of above, it is possible of incorporating the IR temperature measurement device in a cellular phone. As shown in  FIG. 1 , a commercially available IR temperature measurement device  10  comprises an IR sensor  11  and an ASIC (application specific integrated circuit)  12 . The ASIC  12  is adapted to amplify, correct, compensate, and perform an A/D (analog-to-digital) conversion with respect to analog data obtained by the IR sensor  11 . Such processed data is sent to an I2C (inter-integrated circuit) of a bus prior to output.  
         [0016]     As shown in  FIG. 1 , the ASIC  12  comprises five pins, namely, a power (VDD) pin operative in the range from 2.5V to 3.6V, an I2C data (DATA) pin, an I2C clock (CLOCK) pin, a ground (GND) pin, and an active (ACTIVE) pin. When the ACTIVE pin receives a low level signal, the IR temperature measurement device  10  begins to measure temperature. To the contrary, when the ACTIVE pin receives a high level signal, the IR temperature measurement device  10  stops the measurement.  
         [0017]     A CPU (central processing unit) of cellular phone has at least one I2C in its bus. Thus, the IR temperature measurement device  10  can be easily incorporated into the circuitry of cellular phone.  
         [0018]     Referring to  FIG. 2 , there is shown a preferred embodiment of cellular phone  30  having the IR temperature measurement device  10  incorporated into its circuitry. As shown, a power supply IC (integrated circuit)  20  is adapted to supply power to the IR temperature measurement device  10 . The I2C DATA pin and the I2C CLOCK pin of the IR temperature measurement device  10  are coupled to an I2C DATA pin and an I2C CLOCK pin of a CPU  31  of the cellular phone  30  respectively. At the same time, a GPO1 (general purpose output) pin and a GPO2 pin of the CPU  31  are adapted to control the power supply of the power supply IC  20  and the start or stop of the IR temperature measurement device  10  respectively.  
         [0019]     In  FIG. 2 , the GPO1 pin of the CPU  31  is coupled to an enable (EN) pin of the power supply IC  20  so that the power supply IC  20  can be enabled again as commanded by an instruction received from the CPU  31  via the EN pin once an interrupt is removed. In an unused state (i.e., no temperature measurement), power supply to the IR temperature measurement device  10  is cut so as to prolong the operating time of the battery in the cellular phone  30 .  
         [0020]     Moreover, the GPO2 pin of the CPU  31  is coupled to the ACTIVE pin of the IR temperature measurement device  10  for controlling the start or stop of the IR temperature measurement device  10 . In an unused state of the IR temperature measurement device  10 , the CPU  31  causes both the GPO1 and GPO2 pins to be in a high level. At this time, the power supply IC  20  in  FIG. 2  is disabled. That is, no power is supplied to the IR temperature measurement device  10 . Also, the VDD pin of the IR temperature measurement device  10  in  FIG. 2  is 0V.  
         [0021]     Referring to  FIG. 3 , there is shown a top view of the cellular phone  30  incorporating the IR temperature measurement device  10  thereinto. As shown, the cellular phone  30  has the same appearance as a typical one. The cellular phone  30  comprises a phone body  32  including a display  33  for showing data or the like, a keypad  34 , a microphone  35 , a speaker  36 , and an antenna  37 . The IR sensor  11  is formed at one end of the cellular phone  30  spaced from the antenna  37 . The cellular phone  30  is implemented as a hinge type cellular phone in the embodiment shown in  FIG. 3 , while it is appreciated by those skilled in the art that the hinge type cellular phone may be replaced by another type of cellular phone (e.g., a hinge-less type cellular phone (not shown)) in any other embodiments without departing from the scope and spirit of the invention.  
         [0022]     In such a manner, a user may select a “temperature measurement” option of “menu” on the cellular phone  30  for causing the IR sensor  11  to measure temperature. Also, the CPU  31  causes the GPO1 pin to be at a low level. At this time, the power supply IC  20  in  FIG. 2  begins to supply power to the IR temperature measurement device  10 . The power supply IC  20  will supply a constant power after a predetermined period of time (e.g., in the order of several microseconds). And in turn the GPO2 pin is at a low level. At this time, the IR temperature measurement device  10  begins to send the measured temperature data to the CPU  31  via the I2C thereof. The sent temperature data is required to comply with the specifications of the I2C bus. At the same time, detailed temperature data formats can be referred to the specifications of respective IR temperature measurement devices  10  produced by the manufacturers. Note that different IR temperature measurement devices  10  may have different data formats.  
         [0023]     Referring to  FIG. 4 , there is shown an exemplary data format according to the invention. As shown, there are provided data formats of a CLOCK pin, a DATA pin, and a message format to be sent. The message format comprises an Item (item), a MSB (most significant bit), a LSB (least significant bit), a SUM (sum), and a CR (carriage return). In a case of the ACTIVE pin being at a low level, the CPU  31  receives temperature data measured by the IR temperature measurement device  10 . Each record of data is 40 bit long in which Item is 8 bit long for representing data to be sent including ambient temperature, target temperature, system parameters, etc. Specific codes in the Item may be varied depending on the IR temperature measurement devices  10 . Following are a 8 bit high, a 8 bit low, a 8 bit checksum, and a 8 bit data end. The binary temperature data is converted into a corresponding Celsius or Fahrenheit degree prior to showing on the display  33  of the cellular phone  30 .  
         [0024]     Time taken for finishing the above procedure is substantially less than 1 second. Further, temperature update can be done in about 1 to 2 times per second. Hence, it is convenient in use. The precision of the temperature measurement depends on the type of the IR temperature measurement device  10  being used. Generally, after considering the cost factor, a precision in the range of 0.2° C. to 0.5° C. is sufficient for temperature measurement.  
         [0025]     While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims.