姓名: 通訊與電腦整合應用人才培訓第28期 期末測驗試題 課程名稱：CA2801感測元件原理與介面暨量測標準實務
多重選擇 日期: 8/12/2004
acd 1、 下列何者為消除感測元件雜訊(Noise and interference)之有效方法？
(a) 以Shielding的方法可消除電磁干擾.
(b) 以AC Carrier的方法可消除Random noise. (c) 以Autocorrelation的方法可消除Random noise.
(d) 以低通濾波(Low pass filter)的方法可消除高頻noise.
2、 下列何者是將待測物理量轉換成電阻變化？
(a) Piezoelectric sensor (b) Strain gage(應變計)
(c) RTD（Resistive temperature detector） (d) Piezoresistive壓力感測原件 (e) NTC Thermistor
3、 下列有關strain gage之敘述何者正確？
(a) 這種感測元件可用來量測靜態力。 (b) 這種感測元件可用來量測動態力。 (c) 環境溫度會影響感測所得結果之誤差。 (d) 這種元件之輸出是電流，通常要配合電荷放大器使用以得到較正確之電
壓輸出。
(e) 用半導體材料也可以作出這種感測元件。
4、 下列有關Chemoresistor 氣體感測器之敘述何者正確？
(a) 這一類感測元件較常用的Active material是Tin oxide (Sn O2)。 (b) 這種感測器之特性是氣體濃度增加其電阻亦增大。
(c) 其Active material通常需在高溫下工作，所以需予以加熱以致持續消耗
功率。
(d) 運用MEMS技術可以作出較實用之氣體感測器。
5、 今欲以一Hall sensor量導線中之電流
(a) Hall sensor是量磁通密度的元件，所以無法量得導線中之電流。 (b) 此Hall sensor 有四個接腳。 (c) 此Hall sensor 有兩個接腳。
(d) 對定電流之Hall sensor，其厚度愈薄輸出電壓愈大。
bcde abce acd bd be 6、 下列有關熱電耦(thermocouple)之敘述,何者正確？
(a) 熱電耦是一種利用電阻變化的溫度感測器。
(b) 使用熱電耦時需要知道參考點溫度，或使用參考點溫度補償電路。 (c) 半導體材料無法作成熱電耦元件，故其無法應用微感測器技術作熱電
耦。
(d) 熱電耦的輸出是電流，故適合工業上應用。
(e) 應用上可將數故熱電耦串接成熱電堆(Thermopile) ，以增加其
Sensitivity。
7、 請依序寫出下列名詞的相對應解釋：（順序不可改）
（1）Incremental shaft encoder （2）Transducer （3）PTC （4）Load
Cell
名詞解釋：
(a) A temperature sensor
(b) A force sensor
(c) An angular displacement sensor
(d) A sensing device that provides a usable electrical output to a specific
measurand
8、 對一個感測器作Calibration test 時下列何者正確？
(a) 經由Calibration吾人可找出感測器之Sensitivity
(b) 發現感測器之解析度不夠好時，可經由Calibration加以改善 (c) Calibration所用之儀器應比待測之感測器準確 (d) 因一個感測器之特性出廠時有其容許裕度，可經由Calibration加以確定
其數值
(e) 經由Calibration吾人可找出感測器之Non-linearity
9、 一良好的感測元件應具備下列那些條件？
(a) 線性度佳 (b) 解析度高 (c) 頻寬小 (d) 重現性佳 (e) 動態響應快
10、 要決定一個感測元件之 Ideal Straight Line下列何者為必須？
(a) 元件之輸入最小值及其對應之輸出最小值(Imin, Omin) (b) 元件之非線性度 (c) 元件之動態行為
(d) 元件之輸入最大值及其對應之輸出最大值(Imax, Omax)
cdab acde abde ad bc 11、 For a first order element, which method can be used to estimate its time
constant？
(a) Construct a mass-spring-damper system and measure its force-displacement
relation.
(b) Send a step input to the element and record the time response. The time
constant is the time it takes to reach 63.2% of the potential value. (c) Send a step input to the element and record the time response. Draw a
tangent line to the response curve at origin and measure the time duration on the intersection of the potential value.
(d) Increase the operating temperature, and find its sensitivity to temperature.
ac 12、 What are correct statements regarding the dynamic characteristics of a sensing
element？
(a) It is related the how accurate we can measure.
(b) It is related to the application of sensor when measuring DC inputs.
(c) When the response of a sensor is fast, it has good dynamic characteristics. (d) When a sensor is very linear, it must have good dynamic characteristics.
bc 13、 An ultrasonic sensor is used for range measurement
(a) This type of sensor has a very high angular resolution
(b) A electrostatic ultrasonic transducer can be used as a transmitter as well as
receiver
(c) We obtain a distance value from an echo-time counter when using this
sensor
(d) Because sound wave transmits in air, the measurement is not influenced by
the angle between the transducer and the surface of the detected object.
14、 For a piezoelectric force sensor, which statement is correct？
(a) This sensor can generate voltage, so we do not need a power supply to let it
work.
(b) This sensor can generate electric charge, so we do not need a power supply
to let it work.
(c) This sensor can measure static force easily.
(d) The output of this type of sensor is resistive, so a deflection bridge circuit is
used to convert it to voltage. 15、 An AD590 is a semiconductor temperature sensor,
(a) It gives a voltage output from 0 to 5 Volts.
(b) It has a sensitivity of 1 mV/ K, so it must be used with an amplifier.
(c) It has a negative temperature coefficient, so its output resistance decreases
with an increase of temperature. (d) It has a sensitivity of 1μA /K.
b d abc 16、 Piezoresistivity can be applied to make a pressure sensor. Which statement
regarding this type of sensor is correct?
(a) Piezoresistivity can be obtained from doped silicon.
(b) Piezoresistivity-type strain gage has a larger gage factor than that of a metal
foil type strain gage
(c) The type of sensor can be made using IC fabrication technology. 17、 For a two-dimensional Position Sensitive Detector(PSD)
(a) This is a position sensor
(b) This sensor uses photodiode principle.
(c) A signal conditioning circuit must be connected to this device to obtain a
voltage output
(d) This sensor can measure absolute pressure in high accuracy
abc 18、 Select possible applications of a deflection bridge: abc (a) To measure temperature difference using two Platinum resistive temperature
detectors (RTDs)
(b) To measure force using strain gages
(c) To measure position using push-pull capacitive displacement sensors (d) To measure acceleration using piezoelectric quartz crystal. 19、 If a sensor signal has to be transmitted to a control room 100 meters away,
(a) The distance is quite far, a voltage transmission system is preferred.
bcd (b) A current transmission system is a better choice.
(c) An AC carrier system can be used to reduce the influence of 60HZ
interference.
(d) A twist-pair cable can be used to reduce the influence of inductive coupling. ab 20、 What is correct regarding an LVDT,
(a) This is a position sensor.
(b) This sensor operates under an AC excitation power supply.
(c) There are two transformer coils in this sensor, one primary and one
secondary
(d) The output current of this sensor is proportional to the input position to the
sensor.
通讯与电脑整合应用人才培训第28期期末测验试题
