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Active Illumination

Active Illumination, or AI, describes a rapidly evolving range of optical techniques with an increasing impact on scientific enquiry and experimentation. AI has developed over the last two decades alongside the revolution of fluorescent proteins in biology (ref 7, 8), the instrumental and technological developments of confocal laser scanning microscopy (CLSM), solid state light sources (lasers and LEDs), fast galvo and optical MEMS technology, and of course the ubiquitous personal computer. We include among these techniques:

  • Photoactivation and switching
  • Constrained or adaptive illumination
  • FRAP
  • Ablation, cutting and marking
  • Uncaging of caged compounds
  • Optogenetics e.g. channelrhodopsin2

Mosaic & Mosaic Duet

Simultaneous illumination of multiple regions of interest in real time and with zero delta acquisition time

Mosaic is a patented instrument platform built around MEMS Digital Mirror Devices (DMD). DMDs were developed at Texas Instruments in 1987 and are now in widespread use in digital projectors and other display devices. The DMD comprises an array of individually addressable micro-mirrors that can be switched "on and off" (tilted) with MEMS "hinge" elements. DMD arrays contain hundreds of thousands to millions of micro-mirrors.

Mosaic exploits DMD in a proprietary programmable platform, integrated with scientific light sources including lasers, LEDs and arc lamps, and operates from 360 to 800 nm. It is offered with a range of high performance microscope adapter optics and can be integrated with CLSM, spinning disk and wide field imaging modalities.

High speed frame switching (60 Hz) makes Mosaic suitable for many dynamic applications including bleaching, uncaging, photoswitching, optogenetics and constrained illumination. Variable intensity distributions can be achieved by rapid gating of mirror patterns.

Mosaic has a unique capability to illuminate in parallel an arbitrary number of complex regions (sometimes called “zero delta t”) that sets it apart from galvo-based devices and makes it especially attractive for uncaging, photoswitching and light activation. It is a unique tool for the study of optically stimulated intra and inter-cellular activity in neuroscience and physiology, as well as for function-structure studies with photoswitching fluorescent proteins. Mosaic uses dichroic coupling to the microscope light path and is therefore capable of simultaneous stimulation and imaging.

Specifications Summary
Transmission  360 nm to 800 nm
Intensity stability  Absolute
Extinction ratio  > 1000:1
Minimum resolvable spot  Diffraction limited with 100x objective
Optical pixel rise / fall time  < 1 µs
Minimum optical pulse width  60 ms external trigger 100 msec internal trigger
Maximum frame repetition rate  600 frames / sec
Certification  CDRH IIIb (if fitted with a laser source)


Features and Benefits
  • Unlimited flexibility in shape, size, complexity of illumination mask
  • Simultaneous illumination of multiple regions of interest
  • Precise illumination of areas of interest that protects target specimen and fluorophore
  • Zero delta acquisition time for true digital excitation
  • Complementary illumination option enables on and off control in optogenetics studies
  • Longest lifetime and lowest maintenance with rugged semiconductor device


Download Active Illumination Catalogue (8MB)


Simultaneous and precise illumination and ablation

MicroPoint provides a flexible and field-proven tool for photo-stimulation. Supplied with a patented compact, pulsed nitrogen pumped tunable dye laser it is capable of ablation, bleaching and uncaging over a wavelength range of 365 to 656 nm. Broad wavelength range and energy control allow MicroPoint to be optimized for a wide range of scenarios. More than 20 wavelengths can be utilized with available dye resonator cells, while appropriate dichroic filter sets enable simultaneous imaging and photo-stimulation of the specimen. MicroPoint is supplied with a UV-Vis imaging quality Epi illumination adapter for both current and previous generation microscopes from Leica, Nikon, Olympus and Zeiss.

MicroPoint systems consist of a wavelength tuneable pulsed laser, coupling optics, beam steering optics, a microscope adapter, a selection of beam splitters and interference filters, and a motorized or manually driven optical attenuator to adjust spot size and power. There are three MicroPoint versions available:

MicroPoint Manual

Angular and spatial alignment of the illumination at the sample target is manually controlled via a 2-axis joystick. This manual version can be upgraded in-situ to provide galvo or bluetooth control.

MicroPoint Galvo

Galvanometer based beam steering is provided through PC control, enables precise and repeatable laser ablation and/or illumination in synchronization with other experiment parameters.

MicroPoint Bluetooth

In laser marking or circuit isolation applications a computer is often unnecessary, the advanced and automated features of the MicroPoint can be controlled through the handheld PDA interface.

Specifications Summary
Transmission 365 nm to 656 nm
Spectral bandwidth 4 nm FWHM
Transmission variation 0.1%-100%
Resolvable spot size Near diffraction limited
Average power 750 μW, 15 Hz / 50 μJ
Peak power 12 kW
Pulse width 3 to 5 nsec
Pulse repetition rate 0 to 15Hz
Features and Benefits
  • Simultaneous laser delivery, microscope viewing and image acquisition
  • Low maintenance with fiber optic delivery that maintains alignment when system is moved
  • Quick set-up with manual beam positioning or automatic pattern generation
  • User control of ablation and illumination plane provided by z-axis telescope
  • Precise control of energy provided by motorized variable attenuator slide

Download Active Illumination Catalogue (8MB)


Share all laser lines for photo stimulation and imaging

FRAPPA is a galvo scanning instrument, named by conjoining acronyms for fluorescence recovery after photobleaching (FRAP) and photoactivation (PA). FRAPPA has a unique switching design that allows it to be configured in the imaging path. In bypass mode it acts as a relay optic, projecting an image to the detector, while in scanning mode it acts as a laser scanner, targeting user-defined regions of the specimen. This "in-line" configuration allows it to utilize the same wavelength for imaging and photo-stimulation.

The cost of "in-line" operation is sequential execution of imaging and photostimulation, but the switching speed is optimized at ~10 ms to minimize its impact. FRAPPA utilizes galvo technology, has a single laser input and is designed to deliver a diffraction limited spot from CW and pulsed lasers in the wavelength range 400-800 nm.

These features make it an attractive option for photobleaching, switching and activation as well as DNA damage studies.

Specifications Summary
Transmission 400 to 800 nm
Resolvable spot size Near diffraction limited
Laser inpute Single mode fiber FC
Beam power Up to 2 Watts optical
Intensity control AOTF 0.1 to 100%
Laser compatibility Pulsed or CW
Pixel dwell time (minimum) 20 μs
Certification CDRH IIIb


Features and Benefits
  • "Bypass" mode provides 1:1 relay imaging for "in-line" configuration
  • "FRAPPA" mode performs laser scanning via imaging C-port
  • Diffraction limited spot size ~0.6 μm @488 nm FWHM
  • "In-line" operation enables use of all laser lines for FRAPPA actions
  • Mode switching in < 10 ms
  • Integrated control with iQ2 software provides "point-and-shoot" and protocol modes
  • Arbitrary multi-region scanning of points, rectangles and polygons
  • Share imaging lasers with Andor's unique multi-port adapter
  • Active blanking output for ALC integration


Download Active Illumination Catalogue (8MB)