<title>Beam control and diagnostic functions in the NIF transport spatial filter</title>

Abstract

Beam control and diagnostic systems are required to align the National Ignition Facility (NIF) laser prior to a shot as well as to provide diagnostics on 192 beam lines at shot time. A design that allows each beam's large spatial filter lenses to also serve as objective lenses fw beam control and diagnostic sensor packages helps to accomplish the task at a reasonable cost. However, this approach also causes a high concentration of small optics near the pinhole plane of the transport spatial filter (TSF) at the output of each beam. This paper describes the optomechanieal design in and near the central vacuum vessel of the TSF.

Optimal position estimation for the automatic alignment of a high-energy laser

“…Therefore, there are a large number of beam alignment measurements that must be performed along the NIF beam line to assure that the pointing and alignment control system centers the beam in order to provide the maximum energy on the fusion target located in the associated chamber. [1][2][3] An automatic alignment (AA) system was designed and implemented to assure successful deployment of the high energy beam in each of the 192 beam lines. However, since a variety of techniques are provided to perform the alignment, there is a quantifiable uncertainty associated with each technique that may or may not meet the desired accuracy and precision specifications associated at each control point.…”

<title>Overview of small optics for the National Ignition Facility</title>

“…6 In the cavity this includes the LM1 near field light source assembly, the CSF pinhole viewer, an illuminator and a reticle. In the transport section this includes the LM3 near field light source assembly (very similar to the LM1 assembly), a reticle and illuminator, a 1w and a 3w pinhole plane light source assemblies, and a couple of other optics required for the alignment system.…”

Detection of off-normal images for NIF automatic alignment

“…Therefore, there are a large number of alignment measurements that must be performed along the NIF beam lines to assure that the pointing and alignment control system centers the beam in order to provide the maximum energy on the fusion target located in the associated chamber. [11][12][13] An automatic alignment (AA) system was designed and implemented to assure successful deployment of the high energy beam in each of the 192 beam lines. Initially, only four beam lines were constructed and aligned manually by well-trained operators and sophisticated diagnostic tools; however, a fully automated system is close to completion.…”