Instrumentation

Control electronics

Software development

A gas-blending unit for gas LASERS is developed. It is desirable to have specific mixture of two or more gases precisely to optimize the gas flow rates for the lasers, particularly in the developmental stage of gas discharge lasers. This unit can mix three gases typically Helium, Carbon dioxide, and Nitrogen and can provides flow rate up to 20 LPM. Concentration of any gas can be varied from 0.1 to 100 percentage of the full-scale flow.
Another gas blending unit for mixing Hydrogen Bromide and Helium gas is developed. Hydrogen Bromide being corrosive in nature every precaution is taken for the desirable performance of the unit. More over built in purging facility is provided in the unit to protect all gas handling elements including mass flow controller. This unit is to be used for the development of hybrid LASERS

A conventional annunciator system available is bulky because varieties of components are used. A complex programmable logic design (CPLD) based thin, modular and scalable annunciator system is presented. A VHDL technique is used to program CPLD. The complex hardware required is built by CPLD. It reduces the chip count significantly, as a result reliability of system is improved.

A 20-channel (basic module) audio-visual annunciator system is developed to alarm the faults of the critical process parameters of any scientific experiment. It generates the industry standard ISA-1B sequence. It accepts TTL signals from the process monitors and performs logical operation to generate standard annunciator sequence. The output is a 4x5 matrix of windows, with suitable visual devices, displays the status of the process parameters. The acknowledgement and lamp test switches are provided on the window itself for the operator. The unit comprises of Transmitter card (Tx) located in the field, Receiver card (Rx) & window panel at the control room. Tx accepts 20 TTL field signals, converts to serial stream with specific encoding for transmission and modulates it optically. Rx demodulates the incoming signal and converts to 20 parallel status signals and generates individual ISA-1B sequence for each channel. The annunciator operates on serial transmission; means only two wires are required to transmit 20 channels status. Provision is made in the hardware such that transmission can be through optical fiber for high noise environment. If transmission fails, link not ok signal blinks. The unit is developed to monitor the status signals of copper vapor laser. It also finds wide scale applications from R&D to the process control industry. Due to low chip counts and reduced circuit area it is highly suitable for industries having high EMI environment.

Specifications: This EURO standard card is based on P80C552/DS87C550 micro controller, features Powerful and user-friendly monitor and debugger, Various ready to use libraries for. IOs, Print, Math functions, Data acquisition,16 Digital IN buffered Lines,16 Digital Latched OUT Lines., 08 Channels, 10 bit multiplexed buffered Analog Inputs., 02 Lines PWM Outputs.,16 K External ROM., 32 K External RAM.,16-bit Timers and unique noise free Optical / Electrical selectable Serial Communication.Additional 20 lines of I/O from different ports of micorcontroller are provided on the external connector. These lines can be use to interface other peripherals like keypad, LCD and other cards.

Intel 8051 series microcontroller based Process control unit and control cards are developed for various applications. This includes data acquisition , communication on plastic optical fiber link & process control.The process control unit has been succesfuly employed for tough task of CVL control.

Optical isolator cards for digital and analog signals are developed. Digital isolator card handles 14 signals of TTL level on 100mm X 220mm EURO standard PCB. Analog isolator card handles 8 analog signals of 0-10V. These cards offer high isolation in DC and pulsed EMI conditions.

An optical fiber PC serial communication card is developed. It uses a pair of plastic optical fiber to transmit the signal. This card can be directly attached to the PC. This card offers secure communication in high EMI environment, such as laser control.

Pro256c and Pro32Bit are image acqusition and analysis softwares developed for the DOS platform. It acquires image from the EEV modular CCD camera or from the frame grabber cards developed by the Maharshi electronics Ahmedabad and BARC. Initial Promise software was supporting 16 pseudo colors. This software was enhanced with 256 color capability in Pro256c. This software was handling only fixed size image and was using 640 KB of conventional DOS memory. To analyze variable size image and to improve speed of operation Pro32Bit was developed using DPMI features. Promise software is being marketed by Maharshi Electronics, Ahmedabad and is being extensively used by several researchers in CAT, BARC and universities.

PROMISE
PRO256C
Pro32Bit

PROMISE
PRO256C
Pro32Bit

This software is developed for online acquiring, processing and analysis of the B&W and 24 bit true color data from the CCD cameras. It is developed using VB & VC. PromiseC is versatile software for image processing applications and offers special features for scientific measurements e.g. in spectroscopy, laser beam profile, divergence, linewidth, laser produced plasma diagnostics, finding density of the laser cooled atoms, dimensional measurements etc. It can also be used for educational purposes.
Salient features
PromiseC has many capabilities to offer for different measurements. Some of the main options are highlighted below:
* External triggered image acquisition.
* Images upto 16 bit grey scale and 24 bit true color images.
* Intensity profile at any specified direction.
* Direct measurements of beam spot size, linewidth, wavelength and coherence etc.
* Attractive user selectable pseudo color scheme for B&W images
True color images are displayed in combinations of Red, Green and Blue color planes.
* Directional and directional independent edge detection techniques.
* Image smoothing by 3x3 to 9x9 masks.
* Prefixed and user settable masks for Low pass Filters for noise reduction.
* Prefixed and user settable masks for High pass filters for image enhancements.
* Median filtering of 3x3 to 7x7 for removes noise with minimum blurring.
* On-line color stretching provides full-scale color resolution.
* Growth pattern recording with user selectable timing interval.
* On-line multiple image acquiring, adding and averaging for improving signal to noise ratio. On demand individual averaged files are stored to study noise patterns.
* Programmable on-line dark frame subtraction.
* Image operation of inversion, flipping, clipping, rotating and zooming.
* In-built Image editor. Any pixels can be modified, image levels can be enhanced, reduced, multiplied and substituted.
* User selectable image tilting. This helps in aligning along the direction of scan.
* All measurements on the raw as well as on processed image. Processed image can be further processed.
* Simultaneous Line plot of raw and processed image. This pin points the specific features in image processing.
* Built in powerful grapher. Apart from instant viewing compressed line plots, full-scale line plot, at current Horizontal, Vertical cursor positions or at user set angle on the image. Line drawings in many different styles with zooming and clipping. Graph color, scale, title and grid can be selected.
* Multiple intensity plot comparision.
* Moving slit plot for spectroscopic measurements with programable bin height. This plots integrated counts Vs position plot.
* Getting image directly from FG or reading from the disk files. Supports Phs, St6 and 256-color PCX & 8 and 24 bit BMP file format.
* File conversion utility converts .gif, .jpg and .wmf files to .bmp.
* Handles images organized in two interlaced fields.
* Converts RGB image to Gray scaled or Gray scaled to RGB image.
* Any number of files can be added, subtracted and averaged. File can be of mixed type too. Various operation of raw and processed image possible.
* Handles Image size from 16x16 to any length pixel length with 8 to 16 ( 16 bit is converted to 15 ) bits of data resolutions.
* Any of the horizontal or vertical current cursor image line and all the full scale plot data can be saved as a single line file.
* Dynamic color intensity chart. Color stretching depends on full-scale intensity value.
* Image animation. Through this stored images are played, which can provide spot size variation or beam stability information or viewing slow varying phenomena.
* Starts from last settings. No need to configure every time.

This is a 16 bit image acquisition and analysis software for laser produced plasma experiments. (For Laser Plasma Division)

For measuring the time dependent phase of an ultrashort (femtoseconds) laser pulse, using the Frequency Resolved Optical Gating technique (For Laser Physics Division).

For measuring the time dependent phase of an ultrashort (femtoseconds) laser pulse, using the Frequency Resolved Optical Gating technique (For Laser Physics Division).

For acquires profile of the selected laser beam. Software supports 32 cameras (lasers) by using multiplexed frame grabber card. Profile acquiring sequence and its prority can be changed.

Monochromator control and Data acquisition system for studying nonlinearity of the sample using cw or quasi-cw (high rep rate) sources. (For Laser Physics Division)
Salient features of MONOTRIAX
* On-line data / Spectrum acquisition and analysis or off-line analysis.
* Full TRIAX 180 Monochromator control through PC.
* Can be used to control Lock-In through PC.
* Facility of on-line averaging for improves S/N ration.
* Noise removal options.
* Curve fittings and differentiation options.
* Spectrum wavelength can be shifted.
* Wavelength setting and scanning option.
* User calibration option for Monochromator.
* Plots user selected X vs. Y plot.
* Multiple curve comparison.
* Auto Plot scaling for providing best resolution.
* Data acquisition of any 4 user selectable parameter of lock-in amplifier.
* User selectable plot configuration.
* Enlarging of any region of the plot.
* Online facility for making documents.
* Starts from the last settings, no need to set parameters in the beginning.
* Can be used for finding stability, drifting and aging effect.
* Easy to use.

For automated optical density measurement using a scanning microdensitometer. Novel features of the software are:
* Can be used for on-line data acquisition and analysis or off-line analysis.
* Handle very large data files. No limit on the data (film) size.
* Can be used for acquiring data in continuous or in external trigger mode.
* On-line Optical Density calibration.
* Calibration independent of source intensity.
* On-line programmable averaging for reducing the noise.
* For improving signal to noise ratio, various noise reduction techniques.
* Multiple curve comparison with programmable curve shifting.
* Direct Transmission to Optical Density plot.
* Transmission to Intensity plot can also be obtained directly.
* Direct wavelength calibration (any user scale for x-axis) for Intensity plot.
* Auto Plot scaling for (y-axis) providing best resolution.
* User selectable plot configuration.
* Enlarging of any region of the plot for viewing finer details.
* Saves data in different formats ( exporting data for popular packages )
* Online facility for making documents.
* Starts from the last settings, no need to set parameters in the beginning.

Tarang software package is developed for online acquiring, processing and analysis of the data from the USB2000 spectrograph from M/s Ocean Optics. The spectrograph is coupled to the PC through USB port.

Salient features of Tarang
* Can be used for on-line spectrum acquisition and analysis.
* Supports acquiring spectrum in external trigger mode.
* On-line \ off-line programmable spectrum summing to reduce random noise.
* Background spectrum subtraction facility.
* Addition, averaging, subtraction and ratio of spectra can be taken.
* Direct measurement of peak width in nm.
* Novel features of finding stability of the spectrum (on-line \ off-line).
* Makes animation of the spectra.
* Programmable averaging for smoothing the spectrum.
* For improving signal to noise ratio, various noise reduction techniques.
* FFT filtering to remove selected high frequency noise.
* Programmable derivative of spectrum by using various filters.
* Multiple spectrum comparison.
* Auto Plot scaling for (y-axis) providing best resolution.
* User selectable plot configuration.
* Enlarging of any region of the spectrum for viewing details.
* File conversion utility for data exchange with popular packages
* Online facility for making documents.
* Starts from the last settings, no need to set parameters in the beginning.
* Easy to use

PC based Control program for “Gentec” make dual channel Laser Power/Energy Meter was developed. It simultaneously and independently controls both channels. The Laser power meter is connected to PC via serial port [RS232]. It communicates with the unit at 115200 baud rate. Program automatically identifies the power meter head connect to it and configure the scale accordingly. The front end GUI is made identical to the native LCD panel for user convenience. Online acquired data is displayed in large size font suitable for distant reading. The data can be stored with time stamping; the file format is made suitable for Microsoft excel for further processing. This software is developed because power meter LCD display wad damaged and it was unusable. This program was developed for micro machining lab. The program can be used with other “Gentec” make Power/Energy Meter also.