The use of adaptive optics in microscopes allows:
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shifting the depth of focus while maintaining a constant distance between the objective and the object observed. It is thus possible to carry out the microscopy in 3D by section.
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correcting the spherical aberrations introduced by the different optical indices. If not corrected, these aberrations reduce the power of resolution of the microscope. Moreover, the signal of fluorescence is also weakened because of these aberrations.
In the Deformable mirrors tab, you can learn more about ALPAO's very large-stroke mirrors, which permit focusing to a very great depth while correcting large spherical aberrations.
Deformable mirrors: record stroke and exceptional temporal stability in a compact casing.
Unrivalled strokes: +/-45µm of focus and astigmatism
ALPAO has developed an exclusive deformable mirrors technology. Thanks to the large stroke of the mirrors in the Hi-Speed Magnetic Deformable Mirrors range, you will be able to construct a microscope with unparalleled image quality. Thus, by correcting the focus (up to +/-45µm wavefront) and asphericity (up to +/-15µm) aberrations, the PSF of the instrument is very markedly improved, improving the microscope's resolution. Furthermore, the many applications that make use of a fluorescence phenomenon benefit from a reduction in the size of the diameter of the diffraction spot.
Compactness: 1.5mm distance between two actuators!
Thanks to a distance between actuators of 1.5mm and their compact housing, integrating ALPAO's Hi-Speed DM deformable mirrors is easy.
Outstanding temporal response!
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The excellent temporal performance of ALPAO's Hi-Speed mirrors also allows a reduction in the temporal errors traditionally present in large-stroke mirrors. The rise time for a step response is typically equal to 1ms (see figure 2). |
The figure on the left shows the typical Zernike modes that are achievable with the Hi-Speed DM97-15 (wavefront peak-to-valley amplitude). |
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The characteristics of the Hi-Speed DM Series mirror range are summarised in table 1. For more information you can contact us via the site (click here) or you can download the information brochure in the Downloads section.
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Hi-Speed DM52-15 |
Hi-Speed DM69-15 |
Hi-Speed DM97-15 |
Hi-Speed DM277-15 |
| Distance between actuators |
1.5mm |
| Number of actuators |
52 |
69 |
97 |
277 |
| Diameter |
9.0mm |
10.5mm |
13.5mm |
24.5mm |
| Best flat errors (1) |
<7 nm RMS |
| Tip/tilt stroke (wavefront) |
+/- 60 µm Peak-to-Valley |
| Inter-actuator stroke (wavefront) |
> 3.0 µm Peak-to-Valley |
| 3x3 stroke (wavefront, Peak-to-Valley) |
> 30 µm |
> 14 µm |
| Bandwidth (2) |
>750 Hz |
>500 Hz |
| Non linearity errors |
< 3% |
| Hysteresis errors |
< 1% |
| Coating (3) |
Protected silver |
Operating temperature
|
10 - 35 °C |
(1) in closed loop
(2) first resonance of the membrane
(3) All ALPAO mirrors can be treated with different metallic materials (silver, aluminium, gold,...).
The development and integration of adaptive optics systems requires open and flexible control software that can be tuned. The proprietary ALPAO Core Engine (ACE) architecture meets this need perfectly thanks to an open and modular architecture whose principle is represented in Figure 1. The development of a microscope incorporating adaptive optics is thus accelerated.
As the ALPAO Core Engine is a toolbox for Matlab, the user benefits of all this environment to efficiently access to all the data and develop its own control strategy and softwares. For example, the user can use the data from the camera or the wavefront sensor to create a closed loop.
Complementing its offer of custom-made systems, ALPAO offers two standard products initially:
- AOS-0 : system optimised for R&D
- AOS-1: closed-loop system with exceptional performance (500Hz frame rate, low-noise camera, mirror with 241 actuators).
ALPAO AOS-0: Open and flexible system for teaching and R&D
This plug-and-play system has been specially designed for:
- engineers and scientists studying adaptive optics, the laws of control and real-time processing,
- the teaching of adaptive optics.
The AOS-0 workbench includes all the components necessary to simulate a complete adaptive optics system:
- a Hi-Speed ALPAO DM52-15 mirror (including the control electronics )
- a wavefront sensor
- an imaging camera
- a rotating turbulence screen
- an optical source
- the opto-mechanical parts
- Matlab® software to control the system.
- a Matlab® licence (if the user doesn't have one).
Thanks to the ALPAO CORE ENGINE (ACE) architecture and the AOS-0 workbench, it is possible to develop control methods going from the simple law of integration right up to the most advanced solutions such as Kalman filtering. The real-time access to all data (residual errors, wavefront, camera images,.) makes developing your project easier.
The choice of Matlab® allows the user to benefit from the support of the very large user community and the numerous forums associated with it.
Thanks to the AOS-0, you don't need to be a specialist to do adaptive optics but you can become one if you want to!
For more information you can contact us via the site (click here) or by phone or you can download the information brochure in the Downloads section.
> Click here for more information
AOS-1: high-performance adaptive optics loop
The AOS-1 system is based on:
- a Hi-Speed DM241-25 with 241 actuators spread across a diameter of 37.5mm (17 x 17 matrix).
- an ultra-sensitive wavefront sensor manufactured by ALPAO and based on an EMCCD camera (16x16 micro-lenses for the Fried configuration)
- a real-time computer operating at 500 fps and based on the ALPAO Core Engine (ACE).
For more information you can contact us via the site (click here) or you can download the information brochure in the Downloads section.
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