VA charakteristics of LED - Measurement of Planck constant


Note: If more visitors are connected to measurement page, they are ordered in queue by time of visit. Every visitor has approx. 15 minutes to measure, then the measurement is provided to next visitor in queue. This state can be read from status field (eg. Connected, Remaining ... seconds, Max. ... of waiting). When the user is inactive for minutes or the page is closed, his measurement is stopped.


  1. Click on link Run experiment
  2. When the elements of page are loaded, you can see camera and control elements.
  3. Move to the section Choice of LED. By clicking on buttons you choose particular LED with its wavelength.
  4. Move to the section Control voltage for VA characteristics, where you can manually or automaticly change voltage.
  5. In the graph VA characteristics of LED you can see measured data. Each LED is distuingished by its color. Graph can be cleared with button Clear graph.
  6. To start recording measured data, click Start recording in section Data recording. Measure desired data and then click on Stop recording to end recording of data.
  7. Then move to Select recorded data, where new dataset appears. To export them to computer, click on Export values (Excel or HTML table). Download the file (Excel option) or copy data from table (HTML option) from new window by pressing Ctrl + A to select all, Ctrl + C to copy and Ctrl + V to paste in your software.