Automatic Polarimeter – AUTOPOL® I

The AUTOPOL® I is Rudolph’s most economical automatic polarimeter designed for education and less demanding applications where the budget is critical, but quality is still important. The Rudolph Autopol I Automatic Polarimeter is designed for:

  • University – Education Labs
  • Select API’s
  • Vitamins – Nutraceuticals
  • Starch Analysis
  • Lactose in Milk
  • Flavors – Fragrances
  • Chemicals
  • Natural Product Research
  • Invert Sugar

Autopol® I Polarimeter Standard Features:

  • 0.01° Arc Accuracy.
  • 589nm fixed wavelength.
  • Built in thermoprobe for temperature measurement.
  • Windows Embedded OS for direct connection to the network server and flexible USB Printing.

Optional Features:

  • TempTrol™ Automatic Electronic Heating & Cooling 15° – 40°C ±0.2°
  • AP Accuracy Option: 0.004° Arc Optical Rotation
  • AP Resolution Option: 0.01, 0.001° Arc Selectable.
  • USR Resolution Option: 0.01, 0.001°Arc Selectable
  • For USP Pharmaceutical, Rudolph recommends 0.002 accuracy for measurements ±1.000 degrees

Quality Components

Rudolph manufactures its entry-level automatic polarimeter with the same high quality optics as its more expensive instruments. While other manufacturers in this price range use Polaroid Plastic Dichroic Sheet Polarizers, Rudolph does not. Instead, Rudolph uses the same high quality Glan Thompson Calcite Polarizers used in its high accuracy models (Figure A).

Why are high quality polarizing prisms important? Because prisms are two of the most critical optical components in the polarimeter. Polaroid prisms are made of a polymeric plastic where the molecules are stretched and oriented in a specific direction so as to linearly polarize light. These types of plastic sheet polarizers are very inexpensive ($50.00 USD) and are vulnerable to heat, warp over time, deteriorate from moisture, and also have greater light absorption than Calcite Polarizers. In many cases, the plastic polarizers must be replaced in 3 – 5 years. Glan Thompson Calcite Polarizers are comprised of a carbon crystalline structure similar to diamond and have excellent light transmission characteristics. The quality of these prisms is so good, Rudolph guarantees its prisms over the life of the polarimeter.

Polarimeter Sample Temperature

As shown in Figure B, the Autopol® I comes with a Temperature Probe so that sample temperature can be displayed and printed. However, if your product requires Temperature Control, then the Autopol I will most likely not be accurate enough for this type of sample, as is the case for 98% of pharmaceutical applications where a Certificate of Analysis must be issued.

Optional Accessories


Polarimeter Accessories

The Autopol® I is a Single Wavelength Instrument operating at 589nm. The 589nm wavelength is often referred to as the Sodium D-Line. The Autopol® I includes a 100mm or 200mm glass sample cell. A full range of optional Polarimeter accessories are available as shown in Figure C.


All Rudolph Instruments carry our exclusive 20 Commitment to service your instrument.

Rudolph Research Analytical offers a comprehensive range of Preventive Maintenance and Service Programs. Rudolph has demonstrated a commitment to its customers by keeping installed instruments operational, not only for 20 years, but in some cases for over 40 years. This long-term commitment to keeping our instruments running makes the cost of ownership, over the life of a Rudolph Instrument, one of the lowest in the laboratory market segment. At the date this document was published, there is no other laboratory instrument manufacturer guaranteeing service and technical support for 20 years. View the entire 20 Service Guarantee. 


Autopol I – Specifications

AUTOPOL I Polarimeter Specifications
Measuring Mode

Optical Rotation
Specific Rotation
Specific Rotation Plus Concentration
User Defined Scale
Sugar Degrees

Measuring Scale

Degrees Arc Optical Rotation


0.01° Arc Optical Rotation
0.01% Concentration
0.01 Specific Rotation


0.01° Arc Optical Rotation
0.03°Z (ISS) Sugar Degrees

AP Acccuracy Option

Resolution: 0.001° Arc Optical Rotation
Reproducibility: 0.002° Arc Optical Rotation
Accuracy ±0.004° Arc Optical Rotation

AP Resolution Option

AP Selectable Resolution: 0.01, 0.001° Arc


0.01° Arc Optical Rotation

Measuring Range

± 89° Arc Optical Rotation
± 999.99° Arc Specific Rotation
0-99.9% Concentration


Glan Thompson Calcite

Optical Wavelengths


Wavelength Selection


21 CFR Part 11 Compliant Software

Yes with optional PC Software

Temperature Control

By external water bath (Standard)
TempTrol™ Automatic Electronic Heating & Cooling 15° – 40°C
±0.2° (Optional)

Temp. Probe Measurement Range

10° - 100°C

Temp. Probe Measurement Accuracy


Measurement Time

5 measurements in less than 25 seconds (avg.)

Light Source

Tungsten-halogen 6V, 20W, avg. 2,000 hour life

Sample Chamber

Accepts sample tubes up to 200mm

Data Storage

32 GB Non-removable Compact Flash

Communication Interface

3- USB Ports, 1-USB 3.0
2- RS232 serial ports,
Ethernet Port for Network Communication


Automatic calibration via touch screen

Operating System

Windows Embedded

Polarimeter Display

8 inch Color, 800 x 600 pixel resolution with 400 nits of brightness.

User Interface


Automatic Sensitivity Control

Measures samples with transmittance as low as 0.01% (up to O.D. 4.0)

Input Power

100 - 240V, 50/60Hz

Operation Dimensions

24.3"W x 12.7"H x 17.5"D,
617mm W x 323mm H x 432mm D

Shipping Dimensions

31"W x 28"H x 26"D,
787mm W x 711mm H x 660mm D

Operating Weight

42 lbs. (19.05 kg)

Shipping Weight

72 lbs. (32.6 kg)

Calendar/Clock Functions

Battery-backed clock; time and date sent to computer and printer