Eckhardt Optics LLC sells a line of scatterometers based on our conoscopes. For a quick overview, view our brochure here. To turn a conoscope into a scatterometer, we add light sources for transmissive measurements (BTDF) or reflective measurements (BRDF) and appropriate analysis software. The main advantage of a conoscope-based scatterometer is that you get real-time display of the scattering from the sample along with high resolution. Please see our background page on scatterometers for a comparison of the various types of scatterometers. We also have a page on how conoscopic scatterometers work. Below are a few of our conoscopic scatterometers.

conoscopic scatterometers

Scatterometer Features

  • Real-time measurement of bidirectional reflectance (BRDF) or transmittance (BTDF) distribution function, Total Hemispherical Reflectance or Transmittance, Power Spectral Density (PSD), surface roughness and Angular Resolved Scatter
  • Specular measurements with no limitation on the angle between the source and the detector
  • Measurement half-angles from 4° to 80°, depending on the lens
  • Angular resolution of 0.005° to 0.1°, depending on the lens
  • RMS roughness from 5 to 160nm, depending on wavelength
  • Manual or software control over angle of incidence and sample positioning
  • Complete measurements in less than a second

Scatterometer Specifications

  • Measurements BRDF, BTDF, hemispherical transmittance and reflectance
  • Calculations: TIS, PSD, RMS, ABC coefficients for BSDF
  • Wavelength: 405 to 850 nm laser diode or white LED
  • Total System Accuracy: 5%
  • Total System Linearity 2%
  • Repeatability: 2%
  • Dynamic Range: 10 to 16 bits (4096:1 to 65,536:1)
  • Incident Angle Range for Reflection: 0- 80° (depending on the lens)
  • Incident Angle Range for Transmission: 0- 60°
  • Sample X and Y Motion: User Specified
  • Sample Weight: User Specified
  • Computer Interface: USB 3.0
  • Software: Microsoft Windows® based

Scatterometer Options

Camera: Our standard camera is based on a Sony 3 megapixel CCD, which gives us 1450 pixels over the diameter of the image and 10 bits of SNR. If you need higher resolution, we can use cameras with up to 29 megapixels for 3X the linear resolution. We can also use Scientific CMOS cameras for over 14 bits of data.

Light Source: Available light sources include UV, blue, green, yellow, red, near IR and white LED’s that can be configured for either reflective or transmissive measurements. For highest possible resolution, we can use superluminescent LED’s (SLEDs), but these only come in blue, red and NIR.

Control: Our basic scatterometers offer simple and precise manual control of the sample position and angle of incidence. If you prefer, we can motorize these controls and drive them from the software. Contact us so we can configure a scatterometer to meet your measurement needs.