LightMeasure UV Exposure Meters

We offer four versions of meters suited to different situations: A short- and long-UV-wavelength version, with either an internal or an external sensor. All versions have a similar functionality, the main difference being the sensitivity range of the sensor and whether the sensor is mounted internally or externally.


The PPM-1 handheld UV exposure dose meters.

 All meters come with a hard protective case and full instructions. The PPM-2 meters addtionally come with the external sensor (cable length is 18") and an extension cable (length is 36")

The PPM-2 UV meters with external sensors

The PPM-2 external sensor has dimensions 1.75" x 0.9" 0.22" (5.6mm).


The meters are extremely simple to use: Repeated pressing of the green Start/Stop button will toggle the meter between its three modes: 

  1. Reset:  All readings are reset to zero; 
  2. Measure:  The display now shows the current UV intensity, the time in seconds and the accumulated UV dose since the measurement started.
  3. Hold:  The measurement is stopped and the measurements are frozen on the display to allow you to record the information if you choose.
  4. A further SHORT press will return you to step 2 to allow you to continue a measurement (useful for checking progress or while making test-strips), or a LONG press (3 seconds) will take you back to step 1 and reset the meter.


System: The meters consists of a light sensor integrated with optical filters and a microprocessor controller.

Dimensions:  Main unit: 5.7" x 3.5" x 2.1" (length x width x maximum thickness). The PPM-2 external sensor has dimensions:  1.75" x 0.9" 0.22" (5.6mm).

The Display: Consists of a backlit 16 x 2 green display. The information shown is the time, the current UV intensity level, and the accumulated dose of UV light received since the measurement started. The display is angled for convenient viewing.

   -  Time:  The number of seconds since you started the measurement.

   -  IntensityThis reading has many uses: evaluating the intensity of ambient UV levels in the studio, measuring the relative UV transmission of materials, or comparing the UV intensity of different light sources. 

   -  Exposure doseThis is the reading that will be of most frequent use to the artist. It is the total accumulated UV dose received by your print medium since you pressed the start button. Monitoring the dose during the exposure process and stopping once you reach the 'target dose' ensures your prints always receive the same exposure regardless of the intensity of the illumination.

External Sensor Head: The PPM-2 external sensor head has a thin-flat cable allowing it to pass underneath the seal of a vacuum frame. The sensor head will attach magnetically to the front of the control unit making it convenient for hand-held measurements is desired. The sensor is removable for storage. The display indicates 'No Sensor' if measurements are attempted without the sensor being attached.

Battery Operation:  Operates from a standard 9V battery, which is easily replaceable without tools. The display indicates a 'Low Battery' warning once the battery voltage has dropped below 5V indicating the battery should be replaced.

Sleep Mode: the meter will go into sleep mode after 5 minutes of inactivity in order to preserve the battery. Note that this will not happen if you are in the process of making a measurement. Simply press the green button to restore.

Case:  The unit ships with a hard protective case, an instruction booklet, a fresh battery and comes with a one-year warranty against product defects. 

Shipping:  We ship from California, USA. Domestic US shipping:  is via USPS Priority Mail ($7.85). A tracking number will be provided. Shipping typically takes 2 - 3 days.  Click here for details of international shipping

Meters with LONG-UV-wavelength sensors:  350 - 490nm


Meters with SHORT-UV-wavelength sensors:  240 - 370nm