Creating a 3D Energy Density Sensor

This page shows how to create a 3D Energy Density Sensor. This sensor allows you to compute the absorbed energy density in Lumen/m3 or Watt/m3 which can be useful when working with highly diffusive materials, wanting to track some hot spots or wanting to visualize the rays' distribution inside the volume itself.

Important: This feature is only available under Speos Premium or Enterprise license.

To create a 3D Energy Density Sensor:

  1. From the Light Simulation tab, click 3D Energy Density .
    The sensor appears in the 3D view and is placed on the origin of the assembly.
  2. If you want to modify the axis system of the sensor, click to select the origin, to define the X axis and to define the Y axis or click and select a coordinate system to autofill the Axis System.
    Note: If you define manually one axis only, the other axis is automatically (and randomly) calculated by Speos in the 3D view. However, the other axis in the Definition panel may not correspond to the axis in the 3D view. Please refer to the axis in the 3D view.
  3. In General, from the Type drop-down list:

    • Select Photometric if you want the sensor to consider the visible spectrum and get results in lumens/m3.

      Note: In case of a photometric result generation, the International Commission on Illumination (CIE) defines the visible spectrum as follows: "There are no precise limits for the spectral range of visible radiation since they depend upon the amount of radiant flux reaching the retina and the responsivity of the observer. The lower limit is generally taken between 360 nm and 400 nm and the upper limit between 760 nm and 830 nm".
    • Select Radiometric if you want the sensor to consider the entire spectrum and get results in watts/m3.
  4. From the Layer drop-down list:
    • Select None to get the simulation's results in one layer.

    • Select Source if you have created more than one source and want to include one layer per active source in the result.

      Tip: You can change the source's power or spectrum with the Virtual Lighting Controller in Virtual 3D Photometric Lab.

    • Select Face to include one layer per surface selected in the result.

      Tip: Separating the result by face is useful when working on a reflector analysis.

      • In the 3D view click and select the contributing faces you want to include for layer separation.

        Tip: Select a group (Named Selection) to separate the result with one layer for all the faces contained in the group.
      • Select the filtering mode to use to store the results (*.xm3):

      • Last Impact: with this mode, the ray is integrated in the layer of the last hit surface before hitting the sensor.
      • Intersected one time: with this mode, the ray is integrated in the layer of the last hit selected surface if the surface has been selected as a contributing face or the ray intersects it at least one time.
  5. If needed, adjust the dimensions of the sensor by either entering the values or using the 3D view manipulators.
  6. Adjust the sampling of the sensor on X, Y and Z axes.
  7. Press F4 to leave the edition mode.
The 3D Energy Density sensor is created and appears both in Speos tree and in the 3D view.