The Palm Abbe® digital handheld refractometer is unique compared to other digital handheld refractometers thanks, in part, to MISCO’s Optical-Engine™ technology. The Optical-Engine is an integrated measurement engine comprised of a light-source, optics, and measurement electronics assembled into a single, nearly indestructible, module.
How does the Palm Abbe Digital Refractometer Actually Work?
The measurement process begins by modulating a high-intensity LED light source which is specially selected to provide light-energy at precisely 589.3 nm, the sodium D-line, the most common reference wavelength for refractive index measurements. Miniature optical elements and custom filters then focus that light energy on the measuring surface of a sapphire optical element. Sapphire, the next hardest substance to diamond, is virtually unscratchable. Other digital refractometers only have a common glass measuring surface. In the absence of a fluid sample on the measuring surface (Fig. 2) the light-energy is total internally reflected toward a linear detector array.
In Fig. 3, some of the light-energy from the LED is predictably lost into the test fluid. There is a direct relationship between the amount and angles of light-energy lost into the fluid and its critical angle. Past the critical angle, all light energy is internally reflected from the measuring surface where a shadowline is projected on a high-definition detector array with 1,024 individual detector elements, and a resolution of 3,256 pixels per inch (ppi). Compare this to competing refractometers which only have low-definition detector arrays with just 128 elements and a resolution of only 400 ppi. Imagine how much sharper the shadowline image is on the MISCO HD detector array, with 87% more detector elements and more than eight times the resolution. To put it in perspective, it would be like the difference between a 2.5 megapixel camera and a 20 megapixel camera.
Comparing the Palm Abbe to other handheld digital refractometers
Besides the obvious advantages of the MISCO Optical-Engine, the Palm Abbe digital refractometer has a stainless steel sample well and a protective evaporation cover. Most competing refractometers have a plastic well or an anodized aluminum well and no evaporation cover.
The Palm Abbe refractometer has a large 24-character backlit display, which displays the fluid name, the unit of measure, and the actual measurement. Error messages on the Palm Abbe display are displayed as text characters, and it can display them in English, French, German, Spanish, and Russian. Competing instruments usually have just three or four numeric digits, no unit of measure or fluid name display, and error codes are cryptic.
The Palm Abbe refractometer is available with an optional Rubber Armor Jacket, which makes it the most rugged refractometer available and, for a change, it is made right here in the USA, instead of Asia.
MISCO, Optical-Engine, and Palm Abbe are trademarks or registered trademarks in the U.S. and other countries.