Laser Beam Homogenizer
ALBEDO SYSTEM is the technological breakthrough
which will help you to get the best results
for your applications
top hat beam PROFILE
How it works?
The ALBEDO features the latest technical developments from ERROL in terms of beam including the output power, infinity focus, homogeneity and speckle reduction for your applications.
ALBEDO changes a beam profile into a uniform “flat-top”, by combining a multimode fiber input, with a laser speckle reducer and a square -core multimode output fiber.
In most applications, high quality image is required, and single mode fiber is used to couple the laser light. There are disadvantages to using a single mode fiber:
- sensitivity to light drift, making problem in coupling stability, it is due to the core size of the monomode fiber which is the same as the focus laser spot: 3.5 µm
-Power efficiency coupling is about 50%, inherent in the Gaussian intensity profile
-the spectral range is limited: 400-650nm
ALBEDO provides a multimode fiber input.
Multimode fiber advantages:
Long term stability of coupling
Coupling efficiency up to 80%
broadest spectrum of wavelengths 350 to 800 nm
No setting adjustments of coupling needed
The multimode fiber core size is 50µm, when the diameter of the focus laser spot is 3.5µm:
the sensitivity of coupling between the radiation source and fiber to mechanical is drastically reduced,
When the monomode fiber does not tolerate light drift,
ALBEDO has a drift tolerance of 25 µm, x7 the diameter of the laser spot, without any coupling loss.
ALBEDO combines a speckle reducer with a multimode square-core fiber out-put.
ALBEDO uses a rotating diffuser and a vibrating optical fiber to average the interference patterns and provides a uniform square-core shape illumination.
The rotative diffuser breaks the phase and the coherence of the beam to reduce speckle.
The bandwidth of randomizer is 300 kHz.
The square-core multimode fiber provides a uniform “flat-top” intensity profile.
The illumination uniformity is improved by vibrating the multimode fiber. The square-core multimode fiber provides more possibility for ray mixing during light propagation than a circular core multimode fiber.
Also, ALBEDO allows high speed imaging with an exposure time down to 1 ms.
Illustration of monomode and multimode core size
Projection of a 1951 USAF resolution test chart with Albedo
A 1951 USAF resolution test chart is a microscopic optical resolution test device originally defined by the U.S. Air Force MIL-STD-150A standard of 1951. The design provides numerous small target shapes exhibiting a stepped assortment of precise spatial frequency specimens. It is widely used in optical engineering laboratory work to analyze and validate imaging systems such as microscopes, cameras and image scanners.
Laser injection in Square core mulimode fiber of Albedo
from Cladding to Core
Albedo comes in 3 versions
Low frequency 300Hz
Suitable Camera Frame Rate: up to 60Hz
Medium Frequency 300 kHz
Suitable Camera Frame Rate: up to 1 kHz
High Frequency up to 800 kHz
Suitable Camera Frame Rate: up to 10 kHz
ALBEDO Low frequency Box
ALBEDO and LASERS
Medium Frequency Albedo
Suitable Camera Frame Rate: up to 1kHz
One to three Lasers
Suitable with either monomode
or multimode Lasers.
1W Multimode Lasers available
460 / 520 / 635 nm