Stainless steel sample well and IP65 water protection

The stainless steel sample well is easy to clean and corrosion resistant. The ABS thermoplastic casing is built to perform under harsh laboratory and field conditions.

Easy measurement and fast response time

Place a few drops of the sample in the well and press the READ key. These digital refractometers feature a 1.5 second response time.

Small sample size

Sample size can be as small as 2 metric drops.

Automatic Temperature Compensation (ATC)

Measurements are automatically compensated for the effects of temperature for exceptionally accurate measurements.

Unit selection

Pressing the RANGE key quickly cycles through units of measurement when applicable.

Single-point calibration

These digital refractometers offer single-point calibration with distilled or deionized water.

Startup

Battery life and current measurement unit is displayed when powered on.

Battery Error Prevention System (BEPS)

In the event that low battery power could adversely affect readings, BEPS flashes the battery icon on the display. To save battery life, auto shut-off powers down these meters after three minutes.

Refractive Index

Refractive Index is an optical characteristic of a substance and the dissolved particles in it.

The refractive index of a substance is strongly influenced by temperature and the wavelength of light used to measure it. Therefore, care must be taken to control or compensate for temperature differences and wavelength. The refractive index measurements are usually reported at a reference temperature of 20°C (68°F), which is considered to be room temperature.

Refractive index is defined as the ratio of the speed of light in a vacuum to the speed of light in a substance. A result of this property is that light will “bend,” or change direction, when it travels through a substance with a different refractive index. This is called refraction.

When passing from a material with a higher to lower refractive index, there is a critical angle at which an incoming beam of light can no longer refract, but will instead be reflected off the interface between the two substances. This is called total internal reflection.

The critical angle can be used to easily calculate the refractive index according to the equation:

sin (Θcritical) = n2 / n1

Where n2 is the refractive index of the lower-density medium; n1 is the refractive index of the higher-density medium.

A digital refractometer passes an LED light through a prism in contact with the sample. An image sensor determines the critical angle at which the light is no longer refracted through the sample. Specialized algorithms then apply temperature compensation to the measurement and convert the refractive index to the specified parameter.