DE-Series - Direct detection cameras

From Direct Electron

Core piece of the award-winning DE-series cameras is the revolutionary Direct Detection Device (DDD®) sensor which has an exceptional signal-to-noise ratio plus a very high sensitivity and speed.

Transmission electron microscopy (TEM) is a very powerful and commonly used tool to avisualize samples with a resolution in the nanometer or Angstrom range. One limiting factor regarding the final resolution is the general physics in electron scattering which is very strong in the low-dose imaging regime. Beside this the general architecture of the TEM, charging effects, dynamic processes like drift or beam-induced motion of the sample will also have influence on the achievable resolution of your image. Some of these factors can be controlled by the operator but the final resolution will depend on the used detector. The detector will have to meet highest standards with respect to resolution, speed, sensitivity and signal-to-noise ratio. Traditional scintillator-CCD cameras show a clear limitation which was the reason Direct Electron developed as the first manufacturer a new kind of TEM camera architecture. This revolutionary Direct Detection Device (DDD®) sensor was recognized with the 2010 Microscopy Today Innovation Award.

Principle of Direct Detection Device (DDD®) sensors

This new type of sensor directly detects incoming electrons without the need of a scintillator as it would be used in a traditional TEM camera. The incoming electron will pass through a very thin layer leaving an ionization trail. They can now either be counted or integrated. Due to the very low thickness of this layer the normal lateral charge spread is minimized leading to a  much higher resolution compared to other camera architectures. Secondly the architecture of the Direct Detection Device (DDD®) sensor allows a very high frame rate with no dead times between frames which makes this camera extremely useful for any kind of time critical in-situ TEM experiments.

Integrating and counting mode of the Direct Detection Device (DDD®) sensor

The high frame rate and the very high single-electron sensitivity enable the DDD® sensor with two different sensing modes:
  • Integrating mode: The camera will use the total signal which is deposit by each electron on the detector to build the image. This is the most common used operation mode as it is very versatile and fast.
  • Counting mode: This mode has the highest possible performance of the camera but is most effective only for very low dose applications. Every incident electron will be represented by a single count in a single pixel or sub-pixel as it will individually localized, isolated and detected by the camera.
All DE-series cameras can be operated in both modi.

Performance of the cameras

The performance of the cameras can be evaluated using different fundamental or more experimental methods like:

  • Modulation transfer function (MTF)
  • Detective quantum efficiency (DQE)
  • Carbon film Thon rings
  • Experiemental results
Direct DetectorDirect Electron
Pixel Size (µm)6.0 - 6.5
Array SizeVarious sizes up to 8192 x 8192
Pixel Design>3T (CDS to reduce noise)
Frame ShutterGlobal or rolling
BackthinnedYes
Radiation HardnessExcellent
Optimal Exposure RateConsistent performance at any exposure rate
Dynamic Range> 400 e-/pixel/s
Frame RateFlexible; Up to 30 fps, full frame; 1000+ fps for subarrays
Survey SensorIntegrated near-axis 2k × 2k survey sensor
Exposure MeasurementIntegrated Faraday plate above the DDD sensor
Sensor Protection ShutterYes, patented
RetractableYes, mechanical
Sliding O-RingsNo, minimized vacuum spikes during insertion/retraction 
Mounting PositionFilm chamber (JEOL) or bottom-mount
Magnification FactorFilm chamber: 1.0×; Bottom mount: ~1.4×
Data Acquisition SoftwareClient-server model with multiple options:
Micro-Manager (open-source); DE-IM (full-featured); DE-StreamPix (in situ); Open API for integration in custom software.
Movie Processing SoftwareFlexible and open-source; patented algorithms

Currently available DE-series Direct Detection Device (DDD®) sensor cameras:

CameraDE-12DE-20DE-16DE-64
DDD Generation891010
Pixel Size (μm)6.06.46.46.4
Array Size (Pixels)4096x30725120x38404096x40968192x8192
Megapixels12.619.716.867.1
Maximum Frame Rate with Full Array40 fps (bin 1x)
75 fps (bin 2x)
32 fps60 fps (bin 1x)
120 fps (bin 2x)
30 fps
Integrated Survey SensorNone2k x 2k2k x 2k2k x 2k
Typical ApplicationsEconomical general
use direct detection camera
Cryo-EM; DTEM
other low-dose applications
In situ TEM
materials science
Cryo-EM
high-throughput TEM

Contacts

Request further information
Product Manager - Electron microscopy & nanotechnology
+49 6151 8806-12
Fax: +49 6151 8806912

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