Quartz Fiber Electroscope:

The latest electroscope utilizes a quartz fiber and has several benefits over the gold-leaf type. This is portable, much smaller in size, less dependent on position, and more sensitive. A capacity of the quartz fiber electroscope is about 0.2 pico-farads, and their voltage sensitivity is about one volt per division on the scale. A sensitive element is a fine gold plated quartz fiber mounted on a parallel metal support.  Figure describes a quartz fiber electroscope.

Figure: Quartz Fiber Electroscope

A small piece of quartz fiber is mounted across the end of the gold-plated quartz fiber and serves as an index which is viewed by a microscope equipped along with an eyepiece scale.  A quartz fiber is charged through a battery pressing the charging key.  It is deflected from the support as the quartz fiber is being charged.  It takes around 200 volts to generate full-scale deflection of the fiber.  The glass window at the end of the ionization chamber permits for exposure of the fiber.  As the gas (air) is ionized through the incident radiation then the fiber moves toward the position of zero charge.  Because of the electroscope's dependability, accuracy, simplicity, and sensitivity, it is hugely used in gamma radiation measurement.

A self-reading pocket dosimeter is an instance of an electroscope ionization chamber. Pocket dosimeters  gives  personnel  along with  a  means  of  monitoring  their  radiation  exposure. The dosimeters are available in several ranges of gamma exposures from 0 by 200 milliroentgens to 0 by 1000 roentgens. A sensitivity of the instrument is determined at the time of manufacture. Appropriate scale markings are given along with each dose range.