Laser-scanning microscope (LSM) & software

The input of NESSIE is a single laser beam, and the output is a counter-propagating beam collected from the excitation point of the sample.  Our LSM hardware design ensures that the counter-propagating signal does not drift with respect to the input beam as the image is scanned. The NESSIE is therefore ideally suited for adding imaging microscopy to your laser-based experiment.

The software is both user friendly and flexible. We offer a LabVIEW-based software package that incorporates your metrics with our imaging control algorithms. This package generates images in real time and has controls to change the field of view or even fix the laser spot on a single point. We also offer APIs for writing your own code integrate NESSIE with your experiment.

For more information on the capabilities of NESSIE when combined with our BIGFOOT spectrometer, see the Related Products section above.

Fig. 1: Images of GaAs quantum well measured at room temperature using NESSIE. a) White light image measured with camera. b) Laser-scanned linear reflectance measurement with 80 MHz laser (5 mW laser output) tuned to GaAs bandgap. c) Simultaneously measured laser-scanned four-wave-mixing image reveals subsurface defects affecting the GaAs layer.

Custom applications

For integrating with your laser-based laboratory experiment or OEM applications, NESSIE is there. We designed the system to work with a wide range of laser wavelengths and needs.

Two-photon imaging microscopy

Insert NIR light from an ultrafast laser, and detect two-photon emission. Detection requires a short pass filter and a sensitive photodetctor or avalanche photodiode (APD).

Stimulated Raman imaging microscopy (and CARS)

Insert two combined light sources to probe Raman modes, and detect the emitted light using a spectrometer or spectrally filtered photodetector. Conventional SRS uses a narrow band pump and detects a differential pump-probe signal at the wavelength of the probe. For coherent anti-Stokes Raman (CARS), the anti-Stokes signal is blue detuned from the pump and probe. Detection requires a short pass filter and a sensitive detector.

Fluorescence lifetime imaging microscopy

Insert a pulsed light source and detect fluorescence emission using a fast photodetector or avalanche photodiode.

Transient absorption microscopy

Insert an ultrafast laser with a wavelength that is absorbed by the sample. Transient absorption uses either resonant pump and probe, or above resonant pumping, both with detection at the probe wavelength. Detection typically requires an amplified photodetector and lock-in amplification. For high sensitivity and well-integrated software functionality, consider using our BIGFOOT spectrometer to generate and detect the ultrafast pulse sequence.

Adjustable height and large sample area

Designed to operate with commercial cryostats

Cryostats come in many sizes and shapes. Fitting these under a typical microscope requires adapter plates and unstable stages, but not any more! The NESSIE microscope conforms to your sample. The entire microscope can be raised to clear an object with a height less than 4″ to over 8″. The clearance between the center of the objective and the microscope supports and housing is 5.5″.

High stability maintained

By using separate support and lifting mechanisms, we maintain high stability and alignment of the height-adjustable microscope. This stability is essential for generating high resolution images in environments where closed loop cryostats and other equipment generate vibrations.

Laser scanning with no beam offset

Typical laser-scanning microscopes use two X and Y scanning mirrors that are placed near each other to scan the laser. Because neither mirror is at an image plane of the optical system, the beam drifts as the image is scanned. The MONSTR Sense design places both the X and Y scanning mirrors at an image plane, using parabolic mirrors as a relay system between the scanning mirrors, to eliminate the beam drift at the back focal plane of the objective. Parabolic mirrors benefit you by introducing no temporal chirp and negligible loss.

Eliminates vignetting

Vignetting is reduction of image brightness near the image periphery. Though this effect may be great for a photo filter, in microscopy it distorts data and reduces the field of view. Laser scanning using scanning mirrors that are just mounted close together, which is common in commercial and homemade scanning microscopes, introduces substantial vignetting. Our design eliminates this effect over the entire microscope objective’s field of view.

Merging NESSIE with our BIGFOOT ultrafast spectrometer

When combined with our BIGFOOT Ultrafast Spectrometer, the complete system is powerful. Acquire ultrafast movies in seconds, and zoom in on regions of interest for higher resolution scans.

On an overview image select a set of points and completely characterize the electronic and vibrational modes at each of those points with BIGFOOT’s full set of coherent techniques.

Interested in one coherent feature in particular? Measure images with one of our many functional image modes.

The NESSIE microscope is designed to handle a wide range of wavelengths and provide imaging control over the entire microscope objective’s field of view. Imaging controls include: pixel resolution, scan rate, and region of interest. When merged with BIGFOOT, NESSIE allows you to completely correlate electronic structure with spatial inhomogeneity using decay constant maps and hyperspectral images.