| » 20/ 12/ 09 |
| Zeeman Effect Apparatus ( CCD Based ) |
Zeemen effect, splitting of spectral lines under a magnetic field, has been widely acknowledged to be an important phenomena to be experimented by Physics students. It offers deep understanding in atomic physics and quantum mechanics as well as in optics and spectroscopy. Still, many of our physics courses do not include this experiment due to the difficulty in maintaining the conventional zeemen effect apparatus in a student laboratory.
Holmarc’s new CCD based Zeemen effect apparatus is a timely solution. Our apparatus makes the experiment simple to be performed. Equipment is easy to be maintained. The instrument makes use of green light from a common low pressure mercury lamp with the help of a precision Fabry Perot etalon for performing the experiment. CCD camera along with a computer capture the spectral splitting images from the etalon. A group of students can see the phenomena in real time on computer monitor. Students perform calculations and analysis using the images saved in the computer. |
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| Important Features |
► Mercury lamp is used as light source. No special and costly light sources like Cadmium lamp required. Zeemen effect from a common and familiar light source helps students to understand the phenomena better.
► A CCD camera is used to capture the real time image of spectrum from etalon and can be viewed from a computer monitor. The images saved in the computer at various magnetic fields are used for analysis and calculations.
► The equipment is easy to be maintained. All modules and components are locally available. |
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| Modules in the Zeemen Effcet Apparatus |
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High power electro-magnet with power supply.
Gauss meter along with sensor.
Mercury lamp.
Mounted filters and ploarisers.
Fabry- Perot etalon.
CCD camera and software.
Rail and carriage based mechanical mounts for all optics.
Notebook computer (optional inclusion) |
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The apparatus can be used to study normal Zeeman shift of the spectral lines of mercury at λ = 546nm, in fields up to 1.5kGauss. The experiment starts with calibration of electromagnet. Thereafter, optical system is aligned to observe the circular fringes on the computer monitor due to the interference of green light from mercury lamp at the FP etalon. As the magnetic field is increased, the splitting can be observed in real time on the monitor. Images at different magnetic fields are saved in the computer for calculations. Bohr magnetron constant and the e/m ratio are determined from the experiment. |
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| » 09/ 10/ 09 |
| Bench top Rubbing Machine |
We thank you all once again for welcoming this NEWS & EVENTS from Holmarc .
We would like to discuss Bench top Rubbing Machine we have developed for LCD and LCoS R&D Labs. The system is intended for tracing grooves on the polyimide to orient the liquid crystal molecules. The grooves are made using a rubbing cloth wound on a rotating spindle under which the substrate moves at the required constant speed.
The substrate is held by a vacuum chuck for which a vacuum pump is included and integrated with the system. Maximum size of glass substrate which can be loaded is 100 mm x 100 mm.
The substrate along with vacuum chuck is held on a rotation stage so that it can be rotated and positioned at any required angle from 0 to 180 degrees for various rubbing orientations.
The system has been developed as a standalone unit in which speed of the roller and speed of the substrate can be varied. The control can be made through a personal computer as well, if required.
A protective case made from transparent PMMA has also been added to prevent dust and other foreign particles falling on the substrate in operation. |
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| Specifications : |
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1. Substrate holder :
a) Motorized linear stage for substrate movement.
b) Actuated by stepper motor.
c) Travel : 80mm
d) Minimum speed: 0.1mm/sec,
Maximum speed: 10mm/sec
e) Maximum size of movable substrate plate:
100mmx 100mm
f) Substrate fixed on a rotation stage which
can be rotated from 0 to 180 degrees.
2. Rubbing wheel actuator: Brushless DC motor with
speed control
Maximum speed: 3000rpm
Minimum speed: 300 rpm
3. Display of speed on LCD screen
4. Speed control of the spindle by input voltage variation
by a knob
5. Input: 230 V AC
6. The System can be used in standalone mode
as well as in PC mode.
7. Weight of the System: 25 Kgs (approx.) |
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| Programmable Features: |
Movement range for the substrate
Speed of substrate stage
Number of repetitions / Duration of operation |
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