1. Abstract: Nd: YAG laser (Quantel) 1.6J, 8nSec with a repetition rate of 30 Hz is used in the experiment of laser produced plasma. The substrate used in the experiment is a thin film of LiF (0.05  m)-C (0.5  m) coated on Pyrex substrate. As the flash lamp of the Nd: YAG is continuously ON, it has the capacity to ablate the film from the surface of the substrate. To prevent ablation a mechanical shutter assembly is introduced on the path of the laser. This shutter performed as interlock also and it was synchronized with the firing of the laser. The laser is fired on a single shot basis. The Circuit built for the shutter assembly was also used for triggering an ICCD camera so as to take the complete image of the laser produced Plasma Plume. The ICCD camera has inbuilt delay of the 200 nsec, so as to have t = 0, camera has to have a pretrigger of 200 nsec. The circuit controls Laser firing, Shutter opening, ICCD camera and Data Acquisition assembly. Control and Timing Sequence for Laser Produced plasma Institute for Plasma Research, Bhat, Gandhinagar. 382-428 Kiran Patel, S.Sunil, Chhaya, Ajai Kumar Introduction: Laser produce plasma involves ablation of thin film of LiF-C. LiF-C is coated on glass substrate and the film has a thickness of 0.55  m. Ablation procedure involves tight focusing of laser on the target plate using a lens to give spot size of 2 to 3mm and firing of Nd: YAG laser on single shot basis. Once the laser is fired the coating of the film is evaporated and for the next setup of the experiment a fresh coating is needed. This is done manually by a translator mechanism in which target plate is pushed in or pulled out along the axis of the laser. In this paper, an overview of the laser produce Plasma system will be presented, which will focus on the control and timing sequence for laser produce plasma. Basically, Control card design for three different operation First Control Nd:Yag laser to operate in Single shot Mode, Second Open the shutter only for short Duration to pass the laser, and third trigger ICCD camera to capture the image of the Plasma Plum. Description: ND:YAG Laser operated both in Continuous Mode and Single shot Mode. In Continuous Mode, Flash lamp and Q Switch operate continuous at repetition rate of 30 Hz. In Single Shot mode, Flash lamp continuous at 30 Hz but only Q Switch operates in single shot. First, To operate the laser in this mode a trigger pulse required for trigger the Q – Switch and this trigger pulse is come after 300 to 410  sec of Flash lamp Output pulse and flash lamp Output comes at repetition rate of 30 Hz. Second, In Single Shot Mode a Flash lamp continuous ablation of LiF-C coating of plate placed in experimental vessel. When laser is fired, some portion of the LiF-C coating is ablation by flash lamp. To prevent the flash lamp continuous ablation of LiF-C coating a Shutter is placed and shutter is open only shot duration when the laser pulse comes and other time shutter restrict the flash lamp. Control Sequence: To operate Laser in single shot mode, a Trigger Pulse A of 10  sec should be generated with a delay of nearly 300 to 410  sec from Flash Lamp output shown in Fig.2. Delay between Flash Lamp output and Trigger Pulse A is used for to change the Energy of the laser. By varying this delay laser energy change from 1.5 mJ to 3.6 mJ. Shutter required 50-msec duration for 45  of opening and remains open for the next 33 msec in witch at least one pulse comes. Hence, total 83.3 msec pulse required for Shutter.In Fig:3 Main trigger Pulse given from any Pulse Generator and from this trigger pulse a 83 msec pulse generated from monoshot to give a mechanical Shutter. Second a separate Pulse B of 33.3 msec generated from main trigger Pulse with a delay of 50 msec and finally Pulse A and Pulse B are ANDed and generate a Laser fire Pulse. Timing Diagram for Laser Operate in Single Shot External Mode Main Trigger 50 mSec Delay Pulse B 33.3 mSec 83.3 mSec Shutter Pulse Laser Produce Plasma Hardware Overview. SHUTTER LASER EXPERIMENTAL SETUP CONTROL CARD ICCD Timing Diagram for Laser Operation in Single Shot External Mode Delay Pulse 300 – 410 uSec Pulse A 10 uSec 33.3 mSec Flash Lamp Output 45 uSec 10 uSec 710 nSec Timing Sequence for ICCD Trigger 910 nSec Photo Diode Output 10 uSec Laser Fire Pulse PLASMA 2005