GE WEI (CA)
GE WEI (CA)
| GB2034462A | 1980-06-04 | |||
| DE3921951A1 | 1990-12-20 | |||
| GB2200232A | 1988-07-27 |
| 1. | ed are defined as follows: An alarm system (an alarm device or instrument called as Sun UV Alarm, Solar UV Alarm, MED Alarm, Sun UV Dietmate, etc.) which gives solar ultraviolet accumulation alarm, and is used for prevention of skin diseases such as skin cancers caused by absorbing too much solar ultraviolet. A system configuration shown in Figure 1 and Figure 3. A short band solarUV receiving circuit consists of R,, R2, R3, Phototransistor, Zener Diode, Filter and OP,, as shown in Figure 2, which is specifically designed for the solar UV spectrum ranging from 200 nm to 400 nm. 4 A configuration of solarUV accumulation circuit consists of the following parts: (1) a stable voltage supply and a power indication for the accurate sensing and triggering, consist of R,, Zener Diode, R7, R8, LED, ST3 and ST4; (2) a low output impedance solarUV sensing, consists of R2, R3, Phototransistor and OP,; (3) an integrator circuit consists of a phase invertor, an inverse phase integrator and a discharge switch. In Figure 2, this circuit consists of R4, R5, OP,, R^ C, 0P2 and Switch; (4) a Triggering circuit consists of R,, ST, and ST2; (5) a power amplifier consists of OP,, R,0 and R,,; (6) an alarm or alarm and memory, as shown in Figure 2. The said circuits used for detecting and accumulating solarUV strength, and alarm as shown in Figure 4, Figure 5 and Figure 6. SUBSTITUTE SHEET . |
| 2. | Two "Single Supply NonInverting Integration" circuits as shown in Figure 7. |
| 3. | The alarm system in claim 1, claim 2 which accumulates solar UV for 0 to 5 hours in day sun light, and the alarm limit is set to one MED in one day or Permissible 8hour Dose, or Permissible yearly Dose, etc. SUBSTITUTE SHEET. |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the alarm system for detecting the Solar Ultraviolet (referred to as Solar-UV hereafter) and its accumulation (namely absorbed dose by human skins) which is harmful to human skins and may cause skin diseases such as skin cancers if the absorbed dose in certain period exceeds a limit.
2. General Description
It has been proved medically that the absorption of too much solar-UV irradiation can lead to various skin diseases, especially skin cancers. The induction of these skin diseases (including skin cancers) is caused by the accumulation of daily over exposure to solar-UV irradiation over many years. When the accumulation of over exposure to solar-UV increases up to certain value, the skin diseases (including skin cancers) may take place. This invention is intended to warn the over exposure to solar-UV irradiation on the users' skins. When the users are working in the sun or/and taking the sun bath, or/and enjoying the sunshine lying on beaches, users" yards, gardens, they use this invented device (ASSUV) to test the accumulation of the solar-UV irradiation absorbed by their skins, the ASSUV will alarm the users not to be in the sun continuously any more to avoid absorbing too much solar-UV which may cause skin diseases (including skin cancers).
SUBSTITUTESHEET
This invention is a creative and intensive idea which combines the receiving of the solar-UV irradiation, the calculating, and/or memorizing, and/or accumulating and/or alarming, and/or indicating of the portion of solar-UV which is harmful to human beings together. Although there are ultraviolet detectors used in the condition of high temperature ovens to detect the ultraviolet irradiation and protect the health of workers who are working in this surroundings, there is no commercial alarm system for protecting the human skins and health in the solar-UV irradiation.
The ASSUV is very easy to use. When the users are in the sun light, switch on the ASSUV, the skins of users and the ASSUV simultaneously feel the solar-UV irradiation. When the accumulation of the solar-UV increases to a value that is harmful to human skins and may cause skin diseases (including skin cancers), (for example, one Minimal Erythema Dose - MED in one day, or Permissible 8-hour Dose, etc.), the ASSUV alarms the users that over exposure to solar-UV will happen if the users go on exposing to the sun in that day.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is the block diagram of Type-1 ASSUV.
Figure 2 is the schematic circuit of Type-1 ASSUV.
Figure 3 is the block diagram of the ASSUV of Type-2, Type-3 and Type-4.
Figure 4, Figure 5 and Figure 6 are the circuit schemes of the
ASSUV of Type-2, Type-3 and Type-4 respectively.
Figure 7 shows two inventive "single supply non-inverting integration" schemes.
DESCRIPTION OF PREFERRED EMBODIMENTS
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This invention is to detect and accumulate the strength of the solar-UV irradiation, rather than other lights. The ASSUV gives alarm based on the amount of solar UV strength integration. Normally we may use an operational amplifier to construct an invert-phase integration circuit, or we may use more than one operational amplifiers to construct a non- invert-phase integration circuit. In either case, there is at least one operational amplifier which is working in an invert- phase mode. Therefore, we must use split power supply. For battery powered devices, however, it is highly desirable to use single power supply. We invented two "single supply non- inverting integration" circuits for ASSUV (Type-2, Type-3 and Type-4) .
Figure 1 shows the six stages of the ASSUV of type-1. This type of ASSUV uses normal split power supply integration technique. In the first stage, the solar-UV is being detected by a narrow band solar-UV sensor circuit with a spectral range of 200 to 400 nm. This stage transforms the solar-UV strength into a voltage signal. The second stage uses a high input impedance circuit to isolate the first stage from the other circuit, and gives a low output impedance to provide enough power to drive the following circuit. The third stage of the ASSUV of type 1 is an integration circuit which accumulates the solar-UV strength along the time. This accumulation is used as the input signal to Schmitt triggers which is the fourth stage of the ASSUV of type-1. The output signal of the trigger is amplified and used to drive an alarm and a memory which is the final stage of the ASSUV of type-1.
In Figure 2, R ! and the Zener Diode provide a stable voltage source for the solar-UV sensing and the Schmitt triggers, which is critical for the accurate sensing and triggering. The phototransistor and R 2 transform the solar-UV strength into a voltage signal. A high input impedance
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isolator consisting of OP, and R 3 , isolates the solar-UV sensing circuit from the other circuit and passes on the solar-UV strength signal to a phase invertor which consists of OP 2 , R 4 and R 5 . An inverse phase integrator consisting of OP 3 , R 6 and C accumulates the solar-UV strength signal. R, passes on this integral signal to two Schmitt triggers ST, and ST 2 cascaded together. When the solar-UV strength is accumulated to a pre-set level (adjustable by adjusting R , the first trigger ST, gives a low voltage signal to the second trigger ST 2 and ST 2 outputs a high voltage signal. This high voltage signal is power amplified by 0P 4 , R 10 and R„, and is used to drive an alarm and a memory. A power indicator consists of R 7 , R 8 , LED, ST 3 and ST 4 . When a user turns on the ASSUV, the LED lights up indicating the beginning of the solar-UN accumulation, if the LED does not light up, it means that the batteries have no enough power to let the whole circuit work accurately, and should be replaced. The power switch is configured such that when the ASSUV is turned off, the capacitor C is discharged immediately.
The ASSUV's of Type-2, Type-3 and Type-4 have the same block diagram shown in Figure 3. As shown in Figure 3, an ASSUV comprises six parts: SOLAR UV SENSING, SINGLE SUPPLY NON-INVERTING INTEGRATION, BATTERY LEVEL SENSING, THRESHOLD SETTING, VOLTAGE COMPARISON and ALARM SYSTEM. The working processes of these types of ASSUV are described respectively as follows:
1. Type-2 : The circuit scheme is shown in Figure 4.
SOLAR SENSING is made by a photodiode D-, a resistor R, and an operational amplifier OP,. When solar light passes through an optical filter, all other lights are blocked except the UV irradiation which sheds upon the photodiode and generates photo-current. The photo-current passes through R, produces an UV strength signal voltage U uv which is the output
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of the OP,. This UV signal voltage is the input of the next stage.
SINGLE SUPPLY NON-INVERTING INTEGRATION is accomplished by the inventive circuit consists of two operational amplifiers OP 2 and OP 3 , three resistors R 2 , R 3 and R 4 , a capacitor C, and two switches SWITCH, and SWITCH 2 . One of our inventive ideas is to use 0P 2 to transfer the UV signal voltage U uv to R 2 (assuming SWITCH 2 is turned to R 2 ) directly, and thus a current U uv /R 2 flows through R 2 and C,. So the voltage across C, is
- -^/* At (1)
where U c , represents the integral of the solar UV strength. It is a measure of how much solar UV one has received. When U c , reaches a threshold, an alarm is given as a warning for the users. Our another inventive idea is to use OP 3 ^s a high input impedance isolator which is necessary for transferring U cl to the next stage. In equation (1), the factor 1/C,R 2 can be changed to 1/C,R 3 or 1/C,R 4 by SWITCH 2 so as to change the alarm level. When SWITCH, is turned to "power-off", C, is also short circuit and discharged, so that the initial value of the integral is set to zero.
THRESHOLD SETTING is made by a voltage reference D 2 , OP 4 and three resistors R 5 , R 6 and R 7 . R 5 and D 2 provide a reference voltage U D2 which is amplified by OP 4 :
where U^-^--,-, is the triggering voltage set for both solar UV integration alarm and the low battery warning.
BATTERY LEVEL SENSING is made by two resistors R 8 and R,.
VOLTAGE COMPARISON is made by OP 5 and OP 6 . When the amount of solar UV integration is low and the battery is good, both
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outputs of OP 5 and OP 6 are low, no alarm is given; When the amount of solar UV integration reaches the limit, that is
• ^ci ≥ ~ T thrββhold ( 3 ) the output of OP 5 becomes high, this high output drives the alarm system to give the alarm; When the battery is low, that is
U S ≤ U thxβBhold *
the output of OP 6 becomes high, and the alarm system is activated.
ALARM SYSTEM is constructed by two transistors T, and T 2 , four resistors R 12 , R 13 , R 14 and R 15 , four capacitors C 2 , C 3 , C 4 and C 5 , a beeper and a LED.
2. Type-3 : The circuit scheme is shown in Figure 5. Basically this type of ASSUV is the same with Type-2, only except that the input of OP 3 is the output of OP, instead of the inverting-input of OP 2 .
3. Type-4 : The circuit scheme is shown in Figure 6.
This type of ASSUV uses another inventive "single supply non- inverting integration" circuit. It consists of two operational amplifiers OP 2 and OP 3 , five resistors R 2 , R 3 , R 4 , R 5 and R 6 ( or R 7 , or R 8 ) and a capacitor C,. Assuming SWITCH 2 is turned to - , our inventive ideas are to use 0P 3 to feedback the integral signal U c , to the output of UV sensing circuit, and use 0P 2 both as a circuit isolator and an amplifier. By choosing the values of R 2 , R 3 , R 4 , R 5 and R ή , we can get various integral output. If we choose those values such that R 2 =R 3 and R 4 =R 5 , then we have
σ «- 0--.=- i ϋ - dt (5)
Where U c , is the integration of the solar UV strength. The
6
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other parts of this type of ASSUV are the same as those of type-2.
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