感測器原理與應用

•光感測器Light Sensor light dependent resistor (LDR)

A photoresistor or light dependent resistor (LDR) is a resistor whose resistance decreases with increasing incident light intensity; in other words, it exhibits photoconductivity.

http://en.wikipedia.org/wiki/Photoresistor

List of Photodetectorshttp://en.wikipedia.org/wiki/Light_sensor

•光感測器Light Sensor light dependent resistor (LDR)

http://www.seeedstudio.com/depot/grove-light-sensor-p-746.html?cPath=144_148

•電子羅盤3-Axis Digital Compasshttp://www.seeedstudio.com/wiki/Grove_-_3-Axis_Digital_Compass_V1.0

This 3-axis digital compass features a low field magnetic sensing multi-chip module HMC5883L, which provides up to 1° to 2° heading accuracy. HMC5883L consists of high-resolution HMC118X series magneto-resistive sensors.

Magnetoresistance is the property of a material to change the value of its electrical resistance when an external magnetic field is applied to it. http://en.wikipedia.org/wiki/Magnetoresistance

•電子羅盤3-Axis Digital Compass

Magnetic declination is the angle between compass north (the direction the north end of a compass needle points) and true north (the direction along the earth's surface towards the geographic North Pole[1]). The declination is positive when the magnetic north is east of true north.http://en.wikipedia.org/wiki/Magnetic_declination

•電子羅盤3-Axis Digital Compass

Simply speaking, true north is the direction in which the north pole is located along the Earth's rotational axis, while magnetic north is the direction toward which the compass needle points. Magnetic declination varies both from place to place and with the passage of time. http://en.wikipedia.org/wiki/Magnetic_declination

•電子羅盤3-Axis Digital Compass

Correction from Magnetic declinationhttp://www.ngdc.noaa.gov/geomag-web/#declination