With large pixels, high QE, and relatively zero readout noise, EM-CCD technology performs in low light conditions. How low light? When you've got fewer than 10 photons per pixel between the sample and background, EM-CCDs are the perfect tool for the job, delivering the best SNR of any camera technology. For high mag, biologically relevant applications with routine exposure times of 10 ms to 30 ms, the sample is likely emitting hundreds to thousands of photons per pixel. But with faster speeds come shorter exposure times, risking the ability to capture more than tens of photons per pixel in one shot and therefore pushing the application into the ultra-low light zone. The ImagEM X2 makes these super-fast exposures possible and has the sensitivity to provide visually pleasing and quantitatively meaningful images in a photon-starved environment.

By clocking pixel readout at 22 MHz, the ImagEM X2 is able to achieve 70 frames/s with full frame resolution. That's more than 2_ the original ImagEM and is faster than any commercially available camera using the sensor.

Clock: 22 MHz

By selectively imaging at the edge of the sensor, closest to the read register of the chip, it is possible to achieve even greater speeds of small ROIs.

Clock: 22 MHz

In any image sensor, faster readout means increased readout noise. Yet readout noise is considered irrelevant for EM-CCDs because of the EM gain. Remarkably, the ImagEM X2, even before applying EM gain, has faster speed and lower read noise than its predecessor. But didn’t we just say readout noise in EM-CCD was irrelevant? Yes, in SNR equations this is true. However, if the primary purpose of EM gain is to overcome readout noise, then this will be accomplished with less gain in the ImagEM X2 and less voltage in the EM register, translating into theoretically more stable EM gain calibrations and greater sensor longevity.

The ImagEM X2 includes an integrated mechanical shutter in order to protect the camera from EM gain degradation and to lessen afterimage effects. The mechanical shutter is software controlled.

Gain aging is a known and expected process in EM technology. Even when every care is taken to minimize gain aging, use of the camera in EM mode, especially with high gains or high intensity light, can degrade the gain. Since this is a use-dependent phenomenon, it's important to know when it's happened and to have the ability to easily recalibrate. These two functions in the ImagEM X2 make this crucial maintenance of the camera software accessible and user friendly.

The data rates of the ImagEM X2 are well suited to the trusted and easy to use 1394b connectivity.

In its new incarnation, the ImagEM X2 sports four shiny and compact SMA ports, one for input of an external trigger and three for output to other devices. These ports can be used to access an array of triggering options including three additional features: programmable trigger input/output, trigger delay and trigger ready. There is no denying that EM-CCD technology offers the best SNR for ultra-low light imaging, and the ImagEM X2 offers the fastest speeds combined with multiple engineering enhancements to allow you to make the most of this technology.

Output signal can be indicated in "electrons" instead of pixel AD counts in application software.

It enables setting an upper or lower threshold of intensity. If there is a brighter or darker location than a sample of interest in an image, this function allows clipping the upper limit or lower limit of intensity to make Auto LUT function work effectively.

The camera indicates when it has reached the target cooling temperature.

EM gain feature is ideal for live cell imaging because of shorter exposure times and reduced excitation light levels.

The dark current of a CCD depends on the temperature, and it decreases by half when the temperature drops by approximately 7 to 8 ¡C. Therefore, cooling a CCD is a very good way to reduce dark current noise. The ImagEM X2's stable cooling enables stable output and its water cooling minimizes dark current.

Water or forced-air cooling is selectable for any application, and optimal cooling temperature can be set in each cooling mode.

Dark current consists of thermal charge and clock induced charge (CIC). CIC will dominate the dark charge in the images taken at short exposure time, and thermal charge will dominate the dark charge in images taken at longer exposures. The camera is adjusted to use the optimized drive method suitable to the scan speed. The biologist doesn't have to think about CIC optimization for long or short exposures. The camera handles it automatically.

Maintaining stable cooling temperature is essential to stable gain settings required for superior performance in long duration imaging and analysis. Very precise control of the cooling temperature in the ImagEM X2 is a key benefit.

The baseline is constant over time providing signal stability for long term measurements.

It is important to operate the camera in ways that minimize the rate of gain aging and extend the life of the camera. The ImagEM X2 protects EM gain in two levels: EM gain warning and EM gain protection. EM gain protection mode stops charge transfer through the EM gain register when excessive output conditions have occurred which may damage the sensor.

Over time all EM-CCD cameras exhibit gain degradation. The EM gain can be readjusted by raising the voltage in the multiplying register. The EM gain readjustment can be done by software which comes with the camera. However, the number of times the EM gain can be readjusted is limited.
*This feature is available when the camera is operated with DCAM-API. (DCAM-API is a software driver which supports HAMAMATSU digital cameras.)

Select a readout mode for optimal image acquisition based on the sample brightness or desired frame rate or exposure time.

An often overlooked benefit of EM-CCD technology is the ability to utilize the camera as a standard CCD. In non-EM mode, there is no effect of excess noise, and the large full well capacity and high dynamic range are ideal for bright light applications that have large intrascene dynamic range. The ImagEM X2 provides a low read noise non-EM mode that can be an ideal choice for such applications.

This is a unique technology to improve image quality at very low light level to overcome the limitation of excess noise factor from the electron multiplying process. This mode is most useful for signal levels at which maximum EM gain has no apparent signal or very little signal. The mode preserves quantitative linear signal output and also improves spatial resolution at very low light levels.

The following real time processing functions are available.

・Protein-protein interaction
・Calcium waves in cell networks and intracellular ion flux
・Real time spinning disk confocal microscopy
・Single molecule imaging with TIRF microscopy
・Fluorescence in-vivo blood cell microscopy
・Gene expression imaging using luminescence

Specifications