path: root/procedures/chapter.tex

\chapter{Procedures}

\begin{dquote}
  These are the vegetables we must eat before we can have our pixels of ice cream.

  \dsignature{Wright Group saying}.
\end{dquote}

\vfill

In this chapter I document the various procedures that I have performed to maintain the MR-CMDS
instruments.  %

\section{``Six-month'' maintenance}  % ============================================================

The laser system that the Wright Group's MR-CMDS instruments use requires regular maintenance.  %
Each component is sensitive to lab conditions such as temperature, humidity, and vibrations.  %
Small deviations in upstream components can cause large problems in downstream optics.  %
Regular maintenance involves ``tune-up'' of upstream components so that upstream lasers function
well and ideally couple into downstream lasers.  %

Historically, the Wright Group has engaged in reactive maintenance: a ``fix it if it's broken,
don't touch otherwise'' kind of approach.  %
This approach makes a lot of sense for instruments that are quick to fix, and have few active
users.  %
I instituted a proactive, regular maintenance procedure (described below) that has improved the
predictability of instrumental performance.  %
Predictability is key for instruments with multiple users.  %

Supplies needed:
\begin{denumerate}
  \item 5 gallons distilled water.
  \item Filters.
    \begin{denumerate}
      \item 2x 5 micron Liquatec SDF-25-0505
      \item 2x 20 micron general purpose water filter (sold in stockroom)
    \end{denumerate}
  \item Nalco fluids.
    \begin{denumerate}
      \item 4 gallons Nalco 460-PCCL104 (the pink stuff).
      \item 1 gallon Nalco 460-CCL2567 (the clear stuff).
    \end{denumerate}
  \item 150x 5 mg activated charcoal packets (Newport Part \# 90035762) 
\end{denumerate}

Procedure:
\begin{denumerate}
  \item Turn off all lasers in lab.
  \item In no particular order:
    \begin{ditemize}
      \item Computers in lab.
        \begin{denumerate}
          \item Backup contents.
          \item Uninstall unnecessary software.
          \item Update all necessary software.
          \item Restart.
        \end{denumerate}
      \item Chiller maintenance.
        \begin{ditemize}
          \item See \autoref{prc:sec:lytron}
          \item See \autoref{prc:sec:polyscience}
          \item See \autoref{prc:sec:neslab}
        \end{ditemize}
      \item Lab cleaning.
        \begin{denumerate}
          \item Mop the floor, trying to get as much dust as possible. Sweeping in the laser lab is
            discouraged, because it knocks more dust into the air and onto the lasers.
          \item Take out trash.
          \item Empty homeless cables box.
          \item Empty homeless screws box.
          \item Organize any cabling mess.
          \item Remove unused components (optics, electronics, cabling, etc) from laser tables and
            surroundings. Place into appropriate locations.
          \item Organize optics cabinet.
          \item Organize electronics bench.
        \end{denumerate}
    \end{ditemize}
  \item Let lab sit overnight to allow dust to settle and the air to dehumidify.
  \item Start up system again.
\end{denumerate}

\section{Lytron Kodiak RC006} \label{prc:sec:lytron}  % ===========================================

We have one Lytron Kodiak RC006: Model Number RC006G03BB1C002, Serial Number 739383-02.

Regular chiller maintenance:
\begin{denumerate}
  \item Gather supplies.
    \begin{denumerate}
      \item 1 gallon distilled water (do not use deionized)
      \item 1 gallon Nalco 460-PCCL104 (the pink stuff)
    \end{denumerate}
  \item Drain system completely.
    \begin{denumerate}
      \item Turn off chiller.
      \item Break tubing at push-to-connect, plugging return.
      \item Allow chiller to run until liquid stops flowing. You will get a pressure error, ignore
        (silence) it.
      \item Use tube to mouth-syphon remaining liquid from within chiller
      \item Reconnect at push-to-connect
    \end{denumerate}
  \item Fill chiller with distilled water (should require <1 gallon), let run for 30 minutes.
  \item Drain system again.
  \item Replace filter.
  \item Fill system with one gallon Nalco 460-PCCL104 (the pink stuff).
  \item Turn chiller on, top-off with distilled water.
  \item Record maintenance, order new supplies for next time if necessary.
\end{denumerate}

In the past we have had trouble with low flow errors upon system startup.  %
These seem to have been fixed by adding a “high” flow loop connecting the outlet and inlet of the
chiller.  %
Ideally the pressure drop across this loop is sufficient to still drive fluid through the laser.  %

\section{PolyScience 6000 Series} \label{prc:sec:polyscience}  % ==================================

We own two PolyScience chillers---different models but functionally equivalent.

Grey: Serial Number 3E1161245

White and Blue: Serial Number 4K1050550

Regular chiller maintenance:
\begin{denumerate}
  \item Gather supplies.
    \begin{denumerate}
      \item Filter (sold in stockroom).
      \item 1 gallon Nalco 460-PCCL104 (the pink stuff).
    \end{denumerate}
  \item Drain system completely.
    \begin{denumerate}
      \item Disconnect red water line and allow chiller to pump water out.
      \item Push nipple of male end with flat object to release check valve.
    \end{denumerate}
  \item Check filters.
    \begin{denumerate}
      \item If air filter dirty, wash with water (let dry after washing).
      \item If water filter is dirty, replace.
    \end{denumerate}
  \item Reassemble.
    \begin{denumerate}
      \item Fill with Nalco 460-PCCL104 (the pink stuff).
      \item Turn on, top-off with distilled water.
    \end{denumerate}
\end{denumerate}

\section{NesLab Merlin M33} \label{prc:sec:neslab}  % =============================================

We have one NesLab Merlin M33 Chiller, Serial Number 106227049.  %

This chiller serves four different lasers on the ultrafast system.  %
The cycle goes chiller out $\rightarrow$ Millennia $\rightarrow$ Tsunami $\rightarrow$ Spitfire Ace
$\rightarrow$ Spitfire Pro $\rightarrow$ chiller return.

Regular chiller maintenance
\begin{denumerate}
  \item Gather supplies.
  \item Drain system completely.
  \item Clean chiller internals.
  \item Disconnect tubing, plug return.
  \item Remove old filter from chiller, discard, replace filter holder.
  \item Drain system completely and flush with several gallons of distilled water (should require
    2), until no suds are formed as new water goes through system.
  \item Fill system with one gallon distilled water, circulate for at least 15 minutes, then drain
    completely.
  \item Place new filter into chiller.
  \item Reconstruct tubing to include lasers in cycle. Ensure that cycle direction is correct.
  \item Fill system with one gallon Nalco 460-PCCL104 (the pink stuff).
  \item Turn chiller on, and allow system to flow for a while to get air bubbles out.
  \item Top off with distilled water until chiller and tubing is full.
\end{denumerate}

% TODO: figures

\section{Calibrating the 407A}  % =================================================================

Calibrating the 407.A

You may sometimes notice that the zero position changes dramatically from sensitivity to
sensitivity with the 407A. If this happens, iterate through the following until zero stays
consistent:

\begin{ditemize}
  \item Use the fine adjust (knob on side) to zero the 407A on the highest sensitivity.
  \item Use the front adjust (flathead screwdriver needed) to zero on the lowest sensitivity.
\end{ditemize}
    
\section{Millenia}  % =============================================================================

\subsection{Startup}  % ---------------------------------------------------------------------------

The Millennia has problems with ‘thermal runaway’ upon startup if a user naively sends the laser to
4.0 W in power mode (thermal runaway causes the infamous FAULT 146 system shut off: power adjust
timeout error).  %
The following procedure wakes the Millenia up gently enough to prevent thermal runaway.  %
It assumes that the Millenia starts completely shutdown and cold.  %

\begin{denumerate}
  \item Check desiccant inside Millenia, replace if pink.
  \item Ensure that Millenia shutter is closed such that no light is going downstream.  %
  \item Flip orange power switch on diode box.
  \item Wait for system to warm up ($\sim$30 minutes).
    \begin{denumerate}
      \item ``System Warming Up'' message should appear on control box.
      \item Warm-up is finished when percentage complete indicator reaches 100.
      \item The Millenia will start in SP Current mode.
    \end{denumerate}
  \item Record diode hours (choose ``Info'', scroll down).
  \item Turn Millennia to 1.0 W in ``power mode'', wait for equilibration.
    \begin{ditemize}
      \item Equilibration occurs when diode temperature and current are stable (within 0.1) over 5
        minutes.  %
    \end{ditemize}
  \item Switch Millennia to ``current mode''.  
  \item Slowly ramp current until you have more than 4 W output (probably $\sim$70\%).
  \item Again, wait for diode temperature and current equilibration.
  \item Switch Millennia to ``power mode'' at 4.0 W.
  \item Ensure one last time that diode temperature and current are not changing over 5 minute
    timescale.
  \item Measure and record actual Millenia output power, currents, temperatures.
\end{denumerate}

\subsection{Toggling service mode}  % -------------------------------------------------------------

On the control board inside the laser, DIP switch \#4 toggles service mode.  %
Service mode unlocks special SP modes.  %
These allow us to record things like Diode hours.  %
Service mode can be buggy, so it's best to leave the Millenia in normal Power mode during regular
operation.  %

\section{Spitfire Pro}  % =========================================================================

Only tune up the Spitfire if you need to, and do not treat it casually---set aside an entire
day.  %
Merely opening the spitfire box exposes the optics to dust.  %
Treating the Spitfire with the respect it deserves will only save time in the long run.  %

The Spitfire contains 70 charcoal packets.  %
These should be replaced every $\sim$6 months.  %

\subsection{Startup}  % ---------------------------------------------------------------------------

Spitfire Pro startup procedure, from cold.

\begin{denumerate}
  \item Ensure that the software is closed on control laptop.
  \item Turn on Empower power supply (orange switch).
  \item Turn on Timing and Delay Generator ``TDG'' (orange switch).
  \item Turn on temperature control box (orange switch).
  \item Turn key on Empower power supply.
  \item Turn key on TDG.
  \item Start Spitfire software.
    \begin{ditemize}
      \item Often have many faults, most will clear immediately.
      \item Empower LBO temp fault may take a while to clear---normally clears after 5 minutes.
    \end{ditemize}
  \item If Empower has been off (totally, or just at zero amps), warm up at 20 Amps for 1 hour.
    \begin{ditemize}
      \item Use a \textit{good} beam block to block entry into the Cavity during this time.  % TODO: figure
    \end{ditemize} 
\end{denumerate}

\subsection{Common alignment}  % ------------------------------------------------------------------

\subsubsection{Preparation}

\begin{denumerate}
  \item Check desiccant in temperature control box (blue is good, pink is bad).
  \item Connect the fast oscilliscope so that you can see the pulse train.
  \item If Spitfire is off, go through startup procedure.  % TODO: link to section
  \item If it has not been done in awhile, measure and record an Empower power curve.  % TODO: link
    % to section
  \item Place the 407A after the telescope between the large square mirrors on the empty mount.
    \begin{ditemize}
      \item This mount is dedicated for this purpose, and should be left in the Spitfire at all
        times.
    \end{ditemize}
  \item Set Empower current such that the Empower is delivering $\sim$20 W to the crystal (refer to
    Empower power curve).
\end{denumerate}

\subsubsection{Cavity and pump}

The first goal in alignment will be to ensure that the cavity and pump are healthy without
seeding (in ns-lasing mode).  %
A well-aligned Spitfire will deliver 5 to 5.2 W to the 407A when pumped with 20 W.  %
The idea of this procedure is to be minimally invasive, while demanding good performance from the
laser.  %
Do not move on to seeded operation until ns-lasing is healthy, but at the same time do not do more
then you need to.  %

\begin{denumerate}
  \item Switch to ns lasing mode.
    \begin{denumerate}
      \item Block seed at output of stretcher.
        \begin{ditemize}
          \item Note that seed must still enter the stretcher with good enough alignment to defeat
            the bandwidth detector.
        \end{ditemize}
      \item Activate Pockels Cells 2 and 3---do not use Pockels Cell 1.
      \item Expect 20 to 30 ns (2 to 3 round trips) additional build-up time in ns operation.
        \begin{ditemize}
          \item Means you must change timing of Pockels Cell 3 when working in ns lasing mode.
          \item Operate the laser at its ideal switch out time when aligning ns lasing.
          \item Refer to the records to see if your switch-out time is unusual for recent
            performance.
        \end{ditemize}
    \end{denumerate}
  \item Clean all green optics in order of light hitting them.
    \begin{ditemize}
      \item You must get new spectrophotometric grade methanol for this cleaning.
    \end{ditemize}
  \item Loop through the following until ns lasing delivers more than 5 W to the 407A.
    \begin{denumerate}
      \item Check to ensure no optics are damaged, have dust on them etc.
      \item Clean optics. Check power after each cleaning---at the very least you don't want to
        lose power. When cleaning, wait at least a second before letting the light hit the optic
        after cleaning.
      \item Align pump.
        \begin{denumerate}
          \item Decrease the pump power to $\sim$17 A. This should decrease the ns lasing output to
            around 2 Watts, so you should can increase the sensitivity on the 407A if you wish.
          \item Find the ideal switch out (channel 3) time for this lower pump power. It will be
            still later than the aforementioned ns lasing switch out time. Back off the ideal ns
            switch out time by $sim$2 round trips for optimization.
          \item Typically the two mirrors on either side of the cavity (immediate to the lenses)
            are the only pump mirrors touched during alignment. The first pump mirror may be
            touched in special cases but not for regular touch-up.
          \item Block the back reflection with the mirror mount when aligning the second pump
            mirror.  % TODO: figure
          \item Align the back reflection mirror (without beam block).
            \item Iterate through the mirrors until you are satisfied that pump poynting is ideal.
        \end{denumerate}
      \item Align cavity.
        \begin{ditemize}
          \item Never touch anything except the two outermost end mirrors.
          \item Note that the alignment tool is poor to the cavity mode intentionally.
        \end{ditemize}
    \end{denumerate}
\end{denumerate}

\subsubsection{Seed}

Now that the cavity is good, you mus couple the seed into it.  %
If you have just aligned the oscillator you should wait at least 10 hours before attempting to
align the seed.  %

Expect 100 to 150 mW less in seeded mode.  %

\begin{denumerate}
  \item Remove stretcher cavity flange, being careful not to damage wires.
  \item Align the two apertures either side of the Faraday isolator using mirrors external to
    spitfire.
  \item Align to two ``A'' mask positions in stretcher.
  \item Align to three ``F'' mask positions on the way to cavity (this mirror system is
    under-constrained; consider using the final mirror of the ``A'' mask alignment as a tweaking
    mirror).
  \item Let seed into cavity by turning on channel 1.
  \item Optimize (mirror at D18 and periscope) to putput power before compressor---often useful to
    go one or two round trips less ($\sim$210 ns on channel 3) when aligning seed to power (output
    depends on seed more sensitively and you want to optimize for largest buildup reduction
    time).
  \item Can adjust quarter waveplate to minimize post-pulsing if necessary but be very careful to
    not send the output back into the stretcher.
  \item Ensure pulse is let out of the cavity at the optimal time (check oscilloscope and power).
  \item Remove 407A.
  \item Reconstruct flanges on stretcher cavity.
\end{denumerate}

\subsubsection{Output}

Now you must ensure that the cavity output is properly routed through the telescope and compressor
before leaving the Spitfire.  %

Note that only $\sim$80\% of the cavity output power transmits through the compressor due to
absorbance in the grating and other losses.  %

\begin{denumerate}
  \item Align to compressor positions (two ``H'') using backwards alignment tool. You will need to
    unplug the compressor stage cable---remember to plug back in.
  \item If the cavity or pump was touched, consider aligning the compressor.
\end{denumerate}

\subsubsection{Cleanup}

\begin{denumerate}
  \item Make sure you have taken all of your tools out of the laser.
  \item Make sure you remembered to plug the compressor stage back in.
  \item Wait at least 2 hours before moving on to downstream alignment---best to wait overnight if
    you can. It's OK to make a first pass at rough alignment, but compression and pointing will
    probably change slightly as the laser equilibrates.
\end{denumerate}

It's normal for the Spitfire output power change by 50 to 100 mW in the first days after
alignment.  %
After that initial change the Spitfire tends to be stable for weeks.  %
During experiments it's a good idea to measure Spitfire output on a daily basis.  %

\subsection{Stretcher alignment}  % ---------------------------------------------------------------

This is our current best strategy for stretcher alignment.  %
Use caution and keep your brain in gear when working on this.  %
Since we have not messed with the stretcher frequently this guide cannot be trusted blindly.  %

\subsubsection{Preparation}

\begin{denumerate}
  \item Ensure that the Spitfire is off (no pump present in cavity, Pockels cells powered down).
  \item Force upstream oscillator to go CW, adjust output color to be at center of mode-locked
    bandwidth.
  \item Use external mirrors to align through Faraday isolator.
  \item Use first two mirrors after isolator to alignment tool prior to stretcher grating.
\end{denumerate}
  
\subsubsection{Adjustment}

\begin{denumerate}
  \item Adjust the stretcher grating until the four dots are overlapped.
  \item Use pickoff mirror after stretcher to get the beam to alignment tool.
\end{denumerate}
 
\subsection{Compressor alignment}  % --------------------------------------------------------------

\begin{denumerate}
  \item Use the first telescope mirror to align to the alignment tool before the first square
    mirror preceding the compressor.
  \item Use the second telescope mirror to align to the alignment tool when place between the
    square mirrors preceding the compressor.
\end{denumerate}
  
\section{TOPAS-C}  % ==============================================================================

% TODO: figure

\subsection{Common alignment}  % ------------------------------------------------------------------

This section discusses common alignment operations that will probably need adjustment on a monthly
basis to ensure ideal OPA behavior.  %
All fs table users should feel comfortable performing these tuneups.

Tips and tricks:
\begin{ditemize}
  \item As a rule of thumb, if you don't need light through the poweramp the light should be
    blocked to avoid hot spots and damage. The light should be blocked before M8.
  \item Use a fluorescent card to visually get a better idea of the centering of the 800 nm beam
    through the apertures.
  \item Align OPA1 before OPA2. For the sake of consistency, we have agreed that compression should
    be adjusted for OPA1 best performance. OPA2 will have to ``live with'' the compression that is
    best suited for OPA1.
\end{ditemize}

\subsubsection{Preparation}

\begin{denumerate}
  \item Ensure that the Spitfire is working (between 3.8 and 4.0 W).
  \item Ensure that the pump is not clipping on any mirrors between Spitfire and OPAs.
  \item Inspect mode structure of pump for hot spots or diffraction. Clean any dust off of mirrors
    between Spitfire and OPAs.
  \item Open OPA lid.
  \item Set OPA to 1300 nm, ensure motors are homed.
\end{denumerate}

\subsubsection{Preamp}

\begin{denumerate}
  \item Block pump into poweramp upstream of M8 using block of metal.
  \item Open OPA shutter.
  \item Ensure that the WL plate is not drilled---look for ``sparking''. This takes an experienced
    eye---ask if you have a hard time deciding. If drilled, rotate the WL plate.
  \item Ensure that input poynting and compression are good for the preamp by iterating through the
    following adjustments. Stop iteration once all metrics are good without further adjustment.
    \begin{denumerate}
      \item Iteratively align through A0 and A2. The orange-colored white light should go through
        A2.
      \item Ensure that your poynting changes have not introduced clipping on external mirrors.
      \item Ensure that white light is good.
        \begin{ditemize}
          \item If you are aligning OPA1, adjust compression such that WLG is maximized. Do not
            adjust compression to OPA2 WL.
          \item Adjust $A_{WL}$ until WL is symmetric and stable.  % TODO: figure
          \end{ditemize}
      \item Ensure that no OPG is present in C1.
      \item Manually adjust D1 to maximize seed intensity.  
    \end{denumerate}
  \item Align seed down entire row of holes in-which L6, L7, DM2, NC2, and DM3 lie. Alignment is
    accomplished using M5 and M6.
    \begin{ditemize}
      \item Consider blocking pump into C1 (passing only WL) to ``toggle'' the seed---this helps
        distinguish between orange WL and slightly redder seed.
    \end{ditemize}
\end{denumerate}

\subsubsection{Poweramp}

\begin{denumerate}
  \item Unblock pump into poweramp.
  \item Setup 407A power meter outside of OPA.
  \item Adjust manual D2 until over 600 mW is achieved.
  \item Put ``Caution fs OPA free to coldwave'' sign on laser-lab doors.
  \item Remove all optics downstream of Mixer 3: filter periscopes (wavelength selectors),
    periscope, beam splitter, and beam dump.
  \item Iterate the following until optimal power and collinearity are simultaneously reached:
    \begin{denumerate}
      \item Adjust collinearity of three beams using DM2
        \begin{ditemize}
          \item All beams should be overlapped far away.
          \item Use surveyor's telescope to observe beams.
        \end{ditemize}
      \item Maximize 407A-measured power using manual D2.
      \item Maximize 407A-measured power using M10.
    \end{denumerate}
  \item Reassemble optics downstream of Mixer 3.
  \item Close OPA lid.
  \item Allow a minute for equilibration.
  \item Measure and record power---should be over 600 mW.
\end{denumerate}

\subsection{Full alignment}  % --------------------------------------------------------------------

The following discussion endeavors to be as complete as possible.  %
The goal is to have a procedure the produces a well-aligned OPA regardless of initial
conditions.  %
Experienced OPA users may find only pieces of this guide necessary to solve their particular
problem.  %

\subsubsection{Preparation}

\begin{denumerate}
  \item Ensure that the spitfire is working well (between 3.8 and 4.0 W).
  \item Ensure that the pump is not clipping on any mirrors between Spitfire and OPA.
  \item Inspect mode structure of pump for hot spots or diffraction. Clean any dust off of mirrors
    between Spitfire and OPAs.
  \item Open OPA lid.
  \item Set OPA to 1300 nm, ensure motors are homed.
  \item Block pump into poweramp upstream of M8 using block of metal.
  \item Block seed between compensating crystal and M5.
  \item Remove all side walls from OPA.
\end{denumerate}
  
\subsubsection{Input poynting}

Input poynting is adjusted to ensure good alignment through L1 and L2 into D1.

\begin{denumerate}
  \item Remove A1/L3, VF, $A_{WL}$.
  \item Place D2 at nominal position (45 degrees).
  \item Using external mirrors, ensure that beam propagates through the alignment tool at the holes
    just after L2 and just before M1 (in D1).
  \item Ensure that you have not introduced clipping external to the OPA.
  \item Ensure that the L1/L2 telescope is outputting a collimated, undistorted beam.
\end{denumerate}
 
\subsubsection{D1 alignment}

\begin{denumerate}
  \item If you haven't already, remove A1/L3, VF.
  \item Ensure that you are blocking light between compensating crystal and M5.
  \item Remove WLG plate, L4, TD, DM1, knife edge.
  \item Set C1 to surface normal (should be 0 degrees if affix is set correctly in software.)
  \item Using M1 and M2, ensure that beam propagates through the alignment tool at the holes just
    after M2 and just before M5.
\end{denumerate}
 
\subsubsection{White light}

\begin{denumerate}
  \item Block preamp pump after M3 during this procedure.
  \item Remove WL plate if it is present.
  \item Replace/adjust AL/L3, adjusting focus to be at white light plate desired position.
  \item Replace VF and $A_{WL}$ if they are absent.
  \item Replace the WL plate---ensure that the plate is normal to input beam by visual inspection.
  \item Optimize WLG using VF, $A_{WL}$, and plate position.   
    \begin{denumerate}
      \item Begin with $A_{WL}$ closed.
      \item Open $A_{WL}$ 10\%.
      \item Adjust VF to just allow for onset of WLG.
      \item Adjust position of sapphire plate to maximize visible component of continuum.
      \item Adjust VF to attenuate WLG pump to lowest WLG threshold where central mode and first
        outer rings are visible.
      \item Adjust compression for WLG symmetry.
      \item Continue to open $A_{WL}$ and adjust VS until $A_{WL}$ is as open as possible and VF is
        as dark as possible (while maintaining stable WLG).
    \end{denumerate}
  \item Replace / adjust L4.
    \begin{denumerate}
      \item Remove DM1 if it is present.
      \item Adjust L4 so that the visible component of the WL continuum is focused on A2. This will
        ensure that the NIR component focuses at NC1.
      \item Ensure that the WL remains centered on the alignment tool / A2.
        \begin{ditemize}
          \item L4 may be rotated to adjust height.
        \end{ditemize}
      \item Replace DM1. 
    \end{denumerate} 
\end{denumerate}
 
\subsubsection{Preamp pump}

\begin{denumerate}
  \item Remove L5, M4.
  \item Adjust M3 to alignment tool holes near edge of OPA to M5 mount. Note that M3 may be rotated
    to change height.
  \item Ensure that beam is passing through alignment tool near M3. If not, consider translating M3
    or moving BS2. Before making these adjustments ensure that the beam is true into BS2 (see input
    poynting section above).
  \item Replace L5. Ensure that beam through L5 is on-axis with alignment tool in far field.
  \item Replace M4. Point pump so that it intersects with the first red ring in the WL at DM1.
  \item Adjust DM1 to spatially overlap pump with WL in NC1.
  \item Adjust L5 so pump focus in in C1. If OPG in C1 is seen, back-off L5 by moving towards M3
    until OPG disappears.
\end{denumerate}
 
\subsubsection{Seed}

\begin{denumerate}
  \item Ensure that both WL and pump are entering C1 properly.
  \item Remove M5 if present.
  \item Manually adjust D1 to optimize seed generation.
  \item Make fine adjustments to M4 and DM1 to ensure that the seed travels along alignment tools
    all the way to the OPA wall. If large adjustments need to be made something upstream must be
    wrong.
  \item Replace M5.
  \item Replace knife edge, if absent.
    \begin{ditemize}
      \item Ensure you are not clipping the red seed profile.
    \end{ditemize}
  \item Remove L6 and L7 if present.
  \item Use M5 and M6 to align the seed to the alignment guide through C2 and out of the OPA.
  \item Replace L6 and L7.
\end{denumerate}
 
\subsubsection{Poweramp}

\begin{denumerate}
  \item Ensure that pump is not clipping on BS1, M7.
  \item Center pump on M8 using M7.
  \item Remove L8 if present.
  \item Using M8, M9, alignment tool ensure that pump travels along holes from M9 to M10.
  \item Replace L8.
    \begin{ditemize}
      \item Back of L8 Mount to front of M10 should be $\sim$15 cm.
    \end{ditemize}
  \item Without clipping, place M11 and point M10 to minimize off-axis angle at M10 (this requires
    us to put the pump 1/4 inch right of center as viewed while facing M11).
  \item Center pump on M12 using M11.
  \item Center pump on DM2 using M12.
  \item Overlap with seed in NC2 using DM2.
  \item Make small adjustments to M10, DM2 to perfect collinearity and overlap.
  \item Adjust manual D2 until over 600 mW is achived.
  \item Put ``Caution fs OPA free to coldwave'' sign on laser-lab doors.
  \item Remove all optics downstream of Mixer 3: filter periscopes (wavelength selectors),
    periscope, beam splitter, and beam dump.
  \item Iterate the following until optimal power and collinearity are simultaneously reached:
    \begin{denumerate}
      \item Adjust collinearity of three beams using DM2
        \begin{ditemize}
          \item All beams should be overlapped far away.
          \item Use surveyor's telescope to observe beams.
        \end{ditemize}
      \item Maximize 407A-measured power using manual D2.
      \item Maximize 407A-measured power using M10.
    \end{denumerate}
  \item Reassemble optics downstream of Mixer 3.
  \item Close OPA lid.
  \item Allow a minute for equilibration.
  \item Measure and record power---should be over 600 mW.
\end{denumerate}

\section{MicroHR Monochromator}  % ================================================================

Visible Grating.  %

Align the HeNe as perpendicular as possible to the monochromator entrance slit.  %

Move the grating angle until the HeNe falls on the exit slit.  %

Shine a flashlight through the entrance slit and observe the colour on the exit slit: if white,
then you are at 0-order (0 nm), if red, then you are at 1st order (632.8 nm).  %

Go to 0-order, narrow the slits, and slowly adjust the angle until the HeNe is going through the
exit slit.  %

Go to Jovin Yvon/utilities and find the motor configuration program.  %

In the Gratings tab, select the 1st grating (1200 line density) and hit Calibrate.  %

In theoretical wavelength, enter 0 nm.  %

In experimental wavelength, enter the wavelength you observe from the control program.  %

Hit set. %