The Cairn Optosplit image splitter is a simple device enabling a single camera to record images simultaneously at two different optical wavelengths. Traditionally an electronic filter changer or a second camera would be used, neither of which is ideal for all applications. The switching speed of an electronic filter changer limits the system and means that the two images are not truly synchronous. Adding a second camera to an imaging system is expensive and often unnecessarily complicated, because in many instances the region of interest does not require the full resolution of the camera. The Optosplit has been designed as a convenient, inexpensive solution to simultaneous dual wavelength imaging. It has the unique feature of a rotating mirror cradle, which gives adjustable spatial separation, to facilitate image registration. We can also offer a choice between our fixed-centre and new fully adjustable OptoMask rectangular apertures to define the region of interest.

Device drivers are included in several commercial imaging packages to assist registration and to allow realtime and off-line ratioing or fluorescence overlays. Alternatively the Optosplit can be used with simple image capture software and the processing carried out manually off-line. The simple and accessible design makes the Optosplit an excellent platform for alternative applications, such as dual polarisation imaging. Whilst optimised for coupling to a scientific microscope, the Optosplit can also be used with camera lenses or any other system of lenses which produce an image plane of suitable size.

Applications

• Ratio Calcium & pH imaging
• Dual probe imaging
• Fluorescence Resonance Energy Transfer (FRET)
• Total Internal Reflectance Fluorescence (TIRF)
• Polarisation Studies

Features

• Compact design with integral C-mount input and output ports
• Simple & precise controls for image registration
• Interchangeable filter/dichroic holders for dual and single wavelength imaging
• Aperture diaphragms to balance signal levels if appropriate
• Choice of magnification
• Rotating filter mount for polarisation studies (see image)

Cairn Mirror/Filter Cube:

• Our own design of cube accepts 25.4mm interference filters.  
• The dichroic mirror needs to be between 25-26mm wide and between 36-40mm long. Standard Olympus size (26 x 38) works perfectly. We recommend 1mm thickness with our new magnetic style cubes but can accommodate thicker mirrors on request.