The OAV B-ZOOM is an On-Axis Video-microscope with a hybrid zoom system.
It is used for parallax free observation of micrometer sized crystals and is optimized for high-throughput MX crystallography beamlines.
The OAV B-ZOOM is the next evolution of the OAV Ultra-Zoom: it combines the EMBL patented Objective Head of the OAV Ultra-Zoom with a new zooming and visualization module, allowing for instant zoom change. The integrated multi-camera video server supports many new features.
Large working distance
Instant zoom change
Multi-camera video server
Optional high-speed camera at highest magnification
The OAV B-Zoom is equipped with the objective lens system, developed by the EMBL-Grenoble instrumentation group. The lens system has a central hole, coaxial with the optical axis, by which the X-ray beam passes through.
The OAV B-Zoom provides an on-axis visualization allowing in situ perfect alignment of the sample.
The hardware offers x5 and x30 optical magnifications, a numerical aperture of 0.28 and a working distance of 34.8 mm (31.8 mm if a protective glass is added).
Operated with powerful video cameras, the OAV B-ZOOM provides excellent optical performance, with a resolution of 0.16 µm/px @zoom max and 1.9 µm/px @ zoom min. Consequently, the OAV B-Zoom allows to distinguish objects as small as 1 µm or even smaller under optimal conditions.
Instant Zoom Change
The OAV B-Zoom associates two video cameras, one for a « low-zoom » level, and the second for a « high-zoom » level. This hybrid zoom setup uses images from both cameras to emulate a single camera with a large zoom range. With this setup you can switch instantaneously between any of the zoom levels.
This configuration is especially well suited for highly automated end-stations and time critical applications in general. On modern high-throughput beamlines, zooming frequencies of 200 times per day or even more are common. Without motorized mechanics, the OAV B-Zoom is far more reliable than other systems and its instant zoom allows for faster operation.
The zoom level range of the virtual hybrid camera (with 1280 x 1048px) is x2.5 to x30, giving a x12 range. It is possible to go beyond 100% by using up-scaling (interpolation).
Compared to the previous motorized OAV system, the OAV B-ZOOM presents wider range and field. In addition, the OAV B-Zoom provides a series of pre-configuration zoom levels between x2.5 – x12 and between x20 – x30, for which average sharpness is better.
Integrated Video Server
A Video Server designed by Arinax is delivered with the OAV B-ZOOM. The purposes of the server are to:
Accelerate the integration of the 2 cameras into customer applications
which avoids the development of vendor specific camera interfaces. Currently, the server exports several control interfaces (Lima, TANGO, EPICS, HTTP and Redis).
Remove the CPU load burden
of resizing images out of the display application.
Ensure a maximum frame rate
by an optimized C++ program and by using state of the art image processing with up to 60 FPS at full resolution in continuous mode.
Simulate the zoom control
by automatically switching to the right camera and resizing images.
The OAV B-ZOOM is integrated into the MD3-UP diffractometer. Within the diffractometer software, a “three click-centering” function gives the possibility in only three clicks to:
Localize the X-ray beam
Align the sample with the X-ray beam position
Center the sample with respect to the X-ray beam
Supply of a powerful mini-PC with pre-installed imaging software for out of the box imaging with a stand-alone B-Zoom. Simply plug the B-Zoom cameras to the mini-PC and visualize objects, control the zoom level and use imaging tools. You can run the video server on the mini-PC and transport the video stream to another PC e.g., beamline control PC.
Replacement of the camera, which is mounted to the high-magnification column, by a high-speed camera. For a small ROI and at highest magnification, this B&W camera delivers up to 1000 FPS (display with specific desktop application). The high camera speed comes along with a very high light sensitivity and 10 µs exposure at highest magnification. This option is particularly useful for fixed target serial crystallography (SSX).
|Design resolution @max zoom||0.11 µm/px|
|Design resolution @min zoom||1.9 µm/px|
|Hybrid zoom range (combined image)||2.5 to 30|
|Field of view||2.4 x 1.9 mm @ Zoom min;
0.38 x 0.24 mm @ zoom max
|High resolution drilled objective lens||Coaxial hole: 1 mm diameter|
|– Working distance||31.8 or 34.8 mm|
|– Magnification||x5 to x30|
|– Numerical aperture||0.28|
|Spatial resolution||CCD: 2560×2048 px or 2448×2048 px|
|Power supply||USB 3.0|
|Output image size||1280×1024 px recommended. Configurable.|
|Image modes||Simultaneous Raw Images, Auto-selection, Combined|
|Image formats||Mono, RGB, BGR|
|Image transport||TANGO, Redis, Genicam → image streaming, full camera control
http(MJPEG) → image streaming, no camera control
EPICS, Exporter → last image recuperation and camera control (only for gain and exposure) through MicroDiffractometer (MD3/MD2S) app server interface
|Compatible cameras||Genicam, Ueye, Jai, Basler,Prosilica, Mako|
|CPU requirements||22 FPS delivered by the Video Server tested on a PC with one i7-6700 CPU: workload = 25% for two cameras processed in parallel, server output ROI 1280×1024, Bayer conversion included. With cameras in native RGB mode, 18 FPS max, workload = 5%.|
|Width x Height x Depth||94 x 362 x 88.2 mm|