1. Digital Brix Refractometer: This type of refractometer is used to measure the sugar content of a liquid sample. It uses a digital display to show the results and is often used in the food and beverage industry.

2. Handheld Brix Refractometer: This type of refractometer is used to measure the sugar content of a liquid sample. It is a handheld device that is easy to use and is often used in the food and beverage industry.

3. Abbe Refractometer: This type of refractometer is used to measure the refractive index of a liquid sample. It is a more accurate and precise instrument than the handheld Brix refractometer and is often used in the laboratory.

4. Polarimeter: This type of refractometer is used to measure the optical rotation of a liquid sample. It is a more accurate and precise instrument than the handheld Brix refractometer and is often used in the laboratory.