粉底液和粉饼的用法:请问哪里可以找到有关pressure sensor的英文文章？急！！！

http://www.sensorland.com/HowPage004.html

THE PRESSURE SENSOR

With the steam age came the demand for pressure measuring instruments.
Bourdon tubes or bellows, where mechanical displacements were transferred
to an indicating pointer were the first pressure instruments, and are still in
use today.

Pressure metrology is the technology of transducing pressure into an electrical
quantity. Normally, a diaphragm construction is used with strain gauges either
bonded to , or diffused into it, acting as resistive elements. Under the
pressure-induced strain, the resistive values change.

In capacitive technology, the pressure diaphragm is one plate of a capacitor
that changes its value under pressure-induced displacement.

Pressure sensing using diaphragm technology
measures the difference in pressure of the two sides of the diaphragm.
Depending upon the relevant pressure, we use the terms ABSOLUTE, where the
reference is vacuum (1st picture), GAUGE, where the reference is atmospheric
pressure (2nd picture), or DIFFERENTIAL, where the sensor has two ports for
the measure of two different pressure.

The piezoresistive pressure sensor, or silicon cell.

This type of pressure sensor consists of a
micro-machined silicon diaphragm with piezoresistive strain gauges diffused
into it, fused to a silicon or glass backplate.

The resistors have a value of approx. 3.5 kOhm. Pressure-induced strain increases
the value of the radial resistors (r), and decreases the value of the resistors
(t) transverse to the radius. This resistance change can be high as 30%.
The resistors are connected as a Wheatstone Bridge, the output of which is
directly proportional to the pressure.

你可以自己看看这个网址http://www.sensorland.com/HowPage004.html