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- Digital Schlieren System (DSS) BOS method, visualization method
Digital Schlieren System (DSS) BOS method
What is Digital Schlieren?
Schlieren is an optical visualization method developed in the 19th century.
Even if a transparent gas is ejected into the atmosphere, the gas itself cannot be seen directly by the human eye.
However, if the ejected gas and the atmosphere have different densities, the light passing through that part will be refracted, causing a difference in brightness.
What is Schlieren?
What is Digital Schlieren (BOS method)?
Digital Schlieren is one of the so-called BOS (Background Oriented Schlieren) methods that optically visualize density gradients occurring in space.
Compared to the conventional schlieren method, there are very few optical elements, and schlieren images can be easily acquired. Unlike normal foreign matter inspection systems, it is possible to visualize and image objects and phenomena that cannot be visualized.
System features
- Our own integrated software.
Digital Schlieren analysis software [Koncerto-DSS] allows you to complete everything from measurement to analysis on the same software.
*Only using a dedicated camera that is compatible with this software. - Equipped with a variety of analysis algorithms, high-precision BOS analysis is realized (co-developed with Professor Tagawa of Tokyo University of Agriculture and Technology)
The algorithm is developed in-house, and you can choose the subtraction method from a reference image or the sequence method that captures density differences in time-series changes. In addition, as an option, the high-precision BOS analysis algorithm developed in collaboration with Professor Tagawa of Tokyo University of Agriculture and Technology enables highly accurate observation and visualization of minute density differences. - Proposing optimal solutions based on the object of observation and your needs.
We offer a wide range of proposals, from large-scale BOS measurements to visualization on the order of mm.
Since this is a product developed by Seika Digital Image, we can flexibly propose system construction according to your wishes and budget. We can also provide support for visualization methods and joint system development upon separate consultation. - Flexible system design
Our digital Schlieren (BOS method) allows for extremely flexible system design.
For example, if you already have a camera for visualization, you can build a BOS system just by adding software and a background. The components include a high-resolution camera, a high-speed camera, various light sources, and a background (display panel), and the system can be designed according to your needs.
Features
- Simple device configuration with only a camera, background, and analysis software, no lasers, etc.
- Real-time analysis and image display are possible. You can check the phenomenon on the spot
- Installation takes only a few minutes, and preparation for measurement is very easy by using the optional background pattern automatic generation software
- Even if the optical axis is misaligned, recalibration can be performed immediately with the push of a button
- System can be built even with existing cameras
- Compatible with high-speed cameras, allowing high-time resolution measurement
- Wide range, large area measurement is possible
- High-precision BOS algorithm developed in collaboration with Professor Tagawa of Tokyo University of Agriculture and Technology can be selected (optional)
Measurement order
- ① A camera is placed facing the subject, and a dedicated background is placed on the opposite side.
② A base image is obtained in the raw state before the phenomenon occurs (when there is no density gradient).
③ Once the phenomenon occurs, the required number of images are taken at the desired frequency.
④ Once all the data has been captured, the difference from the base image is analyzed using analysis software to calculate a Schlieren image.
System configuration
- Various cameras (high-resolution cameras, high-resolution high-speed cameras)
- Special backgrounds
- Special analysis software
- Special background creation software
- Control PC
merit and demerit
digital schlieren system
- System installation and construction site can be flexibly handled
- Camera, dedicated background unit (including light source) and simple system configuration
- Measurement in a wide area is possible (meter class is also available)
- Acquisition of schlieren images requires post-image analysis
optical schlieren system
- High accuracy for observation in a narrow area (generally several cm to 10-20 cm at most)
- Optical axis adjustment is complicated/It takes time to install/Adjustment requires skill
- There are restrictions on the environment in which the system can be installed (only indoor environments such as laboratories and laboratories)
- The captured image is a schlieren image
Application
- Thermal convection, airflow during combustion
- Visualization of Transparent Gases (e.g., Hydrogen) (Japanese)
- Leaks (Japanese)
- Visualization of pressure and shock waves
- Visualization of indoor airflow and wide-area airflow (tracer-free) (Japanese)
- Observation of heat dissipation conditions (heat transfer in batteries, structures, etc.) (Japanese)
- Inspection of foreign objects in transparent films and monitoring of quality control
Concrete example
- Liquid mixing and stirring process
- cooling, heating phenomenon
- gas leak test
- Thermal convection verification
- Visualization of human exhalation, etc.
- Others Various foreign object inspection and test applications
Measurement Video
Measurement example: Methane gas
Visualization of methane gas being discharged from the tube.
Measurement example: hot plate
It visualizes how air heated from a hot plate rises.
Visualization size (720x420mm)
Measurement example: hot plate flow analysis
It is a vector diagram obtained by flow analysis of the data on the left.
Measurement example: Carbon dioxide gas
Visualizes the carbon dioxide leaking out when opening a carbonated drink.Measurement example: breath
Human breath can be observed. Visualization size (800x800mm)
System configuration list - Digital Schlieren (BOS method) system components Configuration example
The key component of a digital Schlieren (BOS method) system is, of course, the camera.
We configure it according to the application, with high-speed cameras and high-resolution models to suit the movement and speed of the phenomenon to be observed.
We also provide optimal background patterns based on the focal length of the camera and lens, your desired observation range and field of view.
Linked product pages are in Japanese.
High-speed camera reference model
A low-cost, high-sensitivity general-purpose type. Small and easy to handle, it can be used in a variety of applications.
miniAX 200
1,024×1,024@6400fps
12bit , 32GB Memory(MAX)
VEO 710
1,280×800@7500fps
12bit , 72GB Memory(MAX)
HX-7S
1,280×1,072@3,000fps
12bit, 32GB Memory(MAX)
High resolution camera reference model
Supports various high-resolution cameras dedicated to PIV.
DSS-5MP (online display and analysis model)
2,464×2,056, 3.45μm CMOS sensor
12bit, 60fps, 2/3” sensor size
DSS-24MP (online display and analysis compatible model)
5,320 x 4,600, 2.74μm CMOS sensor
12bit, 15fps, 2/3” sensor size
DSS-26MP (not online compatible)
5,120×5,120, 2.5μm CMOS sensor
12bit, 6fps, 2/3” sensor size
Measurement background (Back ground), pattern
Background patterns can be displayed on various displays. *Optional automatic background generation software is required.
If you are using a high-speed camera or want to visualize high-speed flows, we can provide you with a panel with a printed pattern.
We will create the optimal pattern to suit your desired angle of view and field of view.
