The layout of the primary optics

This new compressor layout has been implemented and completed in May 2022. The new layout is a streamlined design, simple, robust, and user-friendly. It has decoupled the time-tool beam. So with time tool overhaul and the new standard configurations, it has executed the PEMP goal successfully in 2022. The new compressor features are listed below:

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In the new compressor system, a complete set of beam pointing imagers are installed to assist the alignment remotely. An online single-shot autocorrelation (SSA), TIPA, is designated for the real-time pulse duration measurement as shown in Fig. 4.

• Input/output pointing imagers:  For the input, CompInFF, CompInNF, and CompG2 are monitoring the far field image behind the 3x telescope, near field image behind the deformable mirror, and the beam pointing on G2. Remotely, SM8 (smartact 8) will be used to center the beam on CompInFF and CompInNF. If the beam pointing is still off on CompG2, M0 can be used to adjust. We also have two cameras (Fig. 2 near field and far field) looking at compressor output. We have three motorized output mirrors (M1, M2, and M3)for adjustment. For output pointing, CompOutNF and CompOutFF are near-field and far-field imagers for output beam

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• after the compression. M1 and M2 can be used to center the beam pointings on CompOutNF and CompOutFF. M3 is used to center the beam to the target chamber reference. 
• Real-time SSA: 1% leak through M2 (99% R mirror) is directed through a side window, a downsize telescope and a 1/2 waveplate into TIPA. The autocorrelation trace can be detected with either MPA1 or MPA2 amplified beam onto a GigE camera. The intensity can be adjusted by 1/2 waveplate. The chirp induced by the glass media (M2, window, and telescope) is

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• measured to be -0.6 mm in the amount of G2 translation. For example, if we obtain the shortest pulse at 11.45 mm G2 translation, the real shortest pulse should be at 11.45-0.65=10.95 (mm). The measurement detail is shown in Fig. 5.

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Figure 4. . a complete set of input/output pointing imagers are installed to assist the alignment remotely. An online single-shot autocorrelation (SSA), TIPA, is designated for the real-time pulse duration measurement.

Performance data

• TiPA measurement: The measurement
• sweet figure
Image Removedwas done with the latest setup as shown in Fig.4 by TIPA. 1% leak through M2 (99% R mirror) is directed through a side window, a downsize telescope, and a 1/2 waveplate into TIPA. The autocorrelation trace can be detected with either MPA1 or MPA2 amplified beam onto a GigE camera. The intensity can be adjusted by 1/2 waveplate.

• • Glass-induced chirp: The plot shown in Fig. 5 is the pulse duration as a function of G2 translation scan. The glass-induced chirp (M2, window, lenses, and waveplate) can be measured by comparing the scans with and without glass media (solid green and empty green) in the air. The lowest point shifting from 12.05 to 11.45 mm suggests that the glass-induced chirp is -0.6 mm in G2 translation.  
  • Vacuum-induced offset: when the chamber is pumped down, the shortest position can be offset due to the removal of air and the breadboard stretch. It turns out the air contribution (um scale)  is much less than the breadboard stretch. We can find out the offset amount by comparing the scans in the air and in the vacuum (solid green and solid red). The lowest point shifting from 12.05 to 11.45 mm suggests that the offset is -0.6mm in G2 translation. 
  • In practice, if we obtain the shortest pulse at 11.45 mm G2 translation, the real shortest pulse should be at 11.45-0.65=10.95 (mm). 

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Figure 5. 

• SSA measurement
  • sweet figure
• SPIDER measurement
  • sweet figure

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