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• Remote controls of grating angle: in the new system, two new rotation motors (URS75BPPV6) for both gratings (Fig1: G1 & G2) were installed to replace the manual controlled rotation stage. The translation stage on G2 was also replaced by LTA, which is encoded and remote-controlled. With all remote-control capabilities, we will implement an in-situ autocorrelator for an auto-optimization procedure, which can be operated with python script.
• Beam path: the beam incidents at the lower beam height in the compressor chamber. The beam goes to G1, G2, retro mirror (to the higher beam height), G2, G1, M1, M2, M3, and then goes to the target chamber. 
• Input/output pointing controlalignment: in for the new systeminput alignment, we have two cameras looking at two input reference points. We have two mirrors prior to the compressor chamber for adjustment. 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.mirrors, T3 and M0 to adjust the beam incident angle to center on two irises, I1 and I2. For output alignment, we use two mirrors, M1 and M2 to center on I3 and I4. For target chamber alignment, we use M2 and M3 to center on I5 and target chamber reference (far-field image) or near-field/far-field imagers in the target chamber.
• Grating parallels: we check grating parallel by setting up a plumb bar near I2 to check the overlap of the shadow on the incident and outgoing beam. 
• Compact mounts: in the new system, we use the 5” in-house designed mirror mounts to replace the 6” ones with lots of disadvantages. We also use compact TRA6 motors to replace LTA motors (cumbersome as pointing motors). The controls of M1x, M1y, M2x, M2y, M3x, M3y, G1 rotation, and G2 rotation are on Newport XPS_1 (mcn-mec-las1). The control of G2 translation is on Newport XPS_2 (mcn-mec-las2).
• Decouple time-tool: in the old system, the time tool beam was leaking through the compressed beam. It created complexity for both alignment and operation. In the new system, time-tool beam is decoupled from this line.
• Upgrading the grating mounts: the grating mounts are redesigned with better stability and compactness. 

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Figure 1. the new layout design: the beam impinge upon the first diffraction grating immediately after entering the vacuum window, from which the beam pointing can be monitored. There are three motorized mirrors M1, M2, and M3 after the fourth bounce of the grating pair G1 and G2 to provide full pointing control prior to propagating into the target chamber.

Layout of diagnostics

we have two cameras looking at two input reference points. We have two mirrors prior to the compressor chamber for adjustment. 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.

Performance data

• TiPA measurement
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• SSA measurement
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• SPIDER measurement
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