The acquisition, guiding, and wavefront sensing units for the large binocular telescope

We present the final opto-mechanical design of the Large Binocular Telescope (LBT) Acquisition, Guiding and Wavefront Sensing Units (AGW-units) together with the laboratory test performance of the units. The units will be installed at the LBT shortly after this conference, at several of the different Gregorian focal positions available. Each AGW-unit consists of a probe with a camera and a wavefront sensor located in front of the science instrument. The probe can move in two axes allowing it to patrol a field off-axis to the science field. A dichroic beam-splitter on the probe transmits the blue light to the acquisition and guide camera and the red light is reflected into a Shack-Hartmann wavefront sensor. The guide camera is equipped with a 2.5x focal reducer giving a field of view of 28"x28" on a 512x1024 frame-transfer CCD. The 12x12 sub-pupil wavefront sensor uses a micro lenslet array made using an ion-exchange technique on a flat substrate with diffraction limited performance.