Theory Of Measuring Opacity Of Rigid Plastics

Light transmission property of the plastic films and rigid plastics are quite difficult to measure and define. As per the current terminology, the materials comprise with the terms such as clarity, total transmittance, transparency, diffuse transmittance, see through resolution distance, opacity, turbidity, haze, translucency, hiding power, etc. In addition to this, several types of measurement are done using the transmission detecting testing devices. The part of the transmission light is scattered in a forward direction outside a certain angle with respect to the normal incident ray. Other methods determine the quantity of resolution in an image which is formed with a particular object with the sheet or film that are placed between the image and object. These measurements describe the optical properties of the material in accordance with the transmittance light of the material.


What is Opacity?

Opacity is that property of a substrate that resists the passage of light. This is calculated by measuring the percentage of the light which is absorbed by a sheet of paper. With a single permit for the light source through your material, the system measures transmission level of the material from 0 to 100 units that help to calculate the percentage of opaqueness and percentage of transparency of the material.

As per the standards, the opacity testing machine is designed to measure the opacity, the percentage of transmittance light which passing through the sample and deviates from the incident ray by forward scattering more than the average. This transmission value bears little relation to the visibility of distant objects that are seen through the samples.

Formula to Calculate Opacity

Opacity of the Material = 100% – Transmittance

For example, if the transmittance of the material is 25.6%, then the Opacity of the material will be,

Opacity = 100% – 25.6%

= 74.4%

One Stop Solution to Calculate Opacity of Rigid Plastics

Numerous manufacturers of testing instruments offer high-quality Opacity Tester to the manufacturers of plastic films and rigid plastics. The instrument is used to test the level of transmittance of the material in order to calculate the opacity of the material. The testing device helps to ascertain the quality of the material.


Presto Stantest, one of the leading manufacturers of the testing device, offers high-quality of Opacity Tester. The instrument is designed as per the Standards that are provided by national and international standardization authorities. The device is designed with two calibration units. SET Zero and SET 100. The device efficiently calculates the transmittance level of the specimen which is clamped in the holder. It is a device designed with a digital meter that provides the readings in a digital readout. The test results of the device help to measure the how much the material is opaque.