Again, we set of about 7am and again we hit traffic miles from Cambridge. It was even worse this week so we didn’t get there until 9am, just time for a cup of tea and for everyone to copy my data stick of data and pictures from last week.
We started the day by trying to catch up with what we missed last week. We eventually got through it all but it was already lunchtime. Now only the afternoon to complete the entire days’ work. Lilly helped us again with our catch-up work in the morning and Daniel for a while in the afternoon.
Daniel brought Katjana in to talk to us as her PhD is largely
about laser ablation which we are working on. Very enlightening – Kat’s short talk enabled us to better understand what we were supposed to be doing and to get on efficiently. Today’s work was about measuring the laser cuts we had done last week so we could establish various properties about the laser power and focus etc.
It was a very long day, especially as I had awoken at 4am and got up at 4.30. We left IfM at Cambridge University around 6.45 and I arrived home at 20.10. I had had to fill the car with petrol on the way home as tomorrow I need to take the hire car back and drive to Bedford to pick up my new car before driving to Cranfield University to continue lectures there.
Probably the best Science University in the World?
We decided to set off early as I know that traffic into Cambridge can be challenging. I picked up Mohamed from Newport Pagnell first at 7am and went onto picking up Rita from her shared house in Cranfield. Rita’s real name is, “Junguo Zhao”, but has chosen an English name because none of us can pronounce it. Ren (Ren Guicun) decided to travel to Cambridge on Wednesday evening, to give himself a little tourist time. Although the traffic was very heavy, we still arrived early at around 8.45am and parked on double yellow lines at IfM (Institute for Manufacturing) as nothing else was available. We wrote a note which was left in the window giving my mobile number etc. and had a quick walk around the campus to take some photo’s.
There are some very modern and colourful buildings along the road fronts with the old buildings behind.
The Cavendish Laboratories are just down the road; this is Rita and Mohammad walking towards them. When we got to the end of the building we bumped into Ran so our quorum was complete.
There were some notable street names, like J.J. Thompson Avenue and Charles Babbage Road etc. Of Course, The Cavendish Laboratories is where Crick and Watson worked when they discovered the form and shape of DNA (National Association for Dyslexics). There were too many famous scientists to mention but a couple, James Clerk Maxwell and Ernest Rutherford. There were also 29 Nobel Laureates from these laboratories.
We still arrived early and in time for a cup of tea and we were off for our first proper lectures. I was also allocated a parking space so moved my car. Today we have two laboratories about measurement (metrology) and we started by being introduced to two microscopes by Daniel, a Cambridge PhD student. I met Daniel on our day out as I sat on the same table for dinner. Daniel is at the end of his PhD and seems to be getting some stick from his peers as he is yet to start writing his thesis.
I used to own a microscope when I was young as I pleaded with my parents to buy me one for a combined Christmas and Birthday one year. They have changed so much since those days mainly because the lighting is so much better and we now have CCTV cameras so the image can be shown on a screen and manipulated by computers. We didn’t even have calculators when I had mine. The sample can be illuminated from the front with lights shining around the viewing lens or from behind like I had. There is also an option to have the light at an angle to show cast shadows.
The post processing option opens a whole new world, for example, you can view samples in 3D by focusing on the top of the sample, then refocusing progressively lower saving each image. The processor knows the focal heights and can stitch the images together enabling you to view the sample from any angle.
We over ran the morning session and therefore our canteen was closed so we had to walk to the West Café, just down the road towards the Cavendish.
We were under pressure from the start in the afternoon when we were introduced to interferometry by Lilly a Cambridge PhD student. I met Lilly on our day out at Cambridge because I sat next to Kryste, her thesis supervisor.
An interferometer microscope is for examining and measuring surfaces. It works by splitting the focal beam, sending one beam directly to the viewing lens and the other via an adjustable mirror. The mirror can be adjusted until interference bands can be viewed caused by diffraction. As all setting are known, measurements can be calculated and interesting images and histograms created.
We were only about half way through our samples when we encountered a problem where the interferometer microscope seemed to view and measure the interference pattern rather than the sample. Lilly couldn’t resolve the problem and brought in an expert, Andy Payne who I also met on our day. Anyway, try as they might our problem remained unsolved when it was late and we all had to go home.
Andrew received his MPhys in Physics from the University of Kent in 2012 where his master’s year research was in Fourier domain optical coherence tomography. Subsequently Andrew joined the Centre for Doctoral Training in Photonic Systems Development and received his MRes from the University of Cambridge after conducting research into the coherence properties of liquid crystal lasers at Cambridge and the registration of 3D laser scanned point clouds at UCL.
We were booked into a Premier Inn only a mile or two away so we headed off and checked in.
To save money, Mohammad and myself were sharing in a “quad” room”, so we unpacked and tidied ourselves up and headed off to the restaurant attached. Rita decided she wasn’t ready to eat and fancied a walk into the centre to have a look around. By the time we had eaten it was 20.30 and we had no response from Rita when we knocked so went to our room to catch up on emails etc. I emailed my computer written notes to the others. I also took my new camera and will share the pictures once I remember a USB stick.
Our first night in Cambridge happened to be Harvest Moon so I took a picture of the
Moon but it was drowned out by the street lamp. Harvest Moon is the full moon that takes place closest to the Autumn equinox. It used to be used to indicate when the crops should be gathered in to prepare for the winter months. The full moon meant that work could go on later because of the extra light before we had street lights.
We all met for breakfast around 7.30 and could have as much as we liked from any menu.
We did our best and headed off to the University. Today we were introduced to lasers by Dr Martin Sparks.
Martin is part of the Cambridge core team and is a senior research assistant.
Again, we all struggled, Martin talked and went through procedures at a tremendous pace and we all struggled to keep up while trying to take pictures and notes in unfamiliar topics. As something had happened to the alignment of the equipment, we had to readjust the mirrors and equipment to get back in alignment again. I am pleased that we had to go through this process because the alignment experience was a real help to understand the process. Starting from the laser source we had to work our way through the system following the beam route adjusting as we went. This meant that we had to wear special goggles, have the covers open and laser on while making these adjustments.
The main purpose of this Lab was to lead us into understanding the importance of documenting everything, thinking about things before acting and, “leaving no stone unturned”. In research it is so important to document everything so that your work can be criticised and repeated to verify if necessary. If anything is left out it leaves doubts over the validity of your work. A good example of this was the research done into room temperature cold fusion.
This day was extremely stressful to us all as Martin left us to work so much out for ourselves. At first, problems seemed insurmountable but gradually, maybe with hints, we got there in the end. The harder things are to solve, the more fulfilling when they eventually are.
In the afternoon, we had a sample that we could blast with the laser, doing experiments, varying power and other things so that these could all be examined using the microscope and interferometer next week. We used G programming language to control the laser cutting process. Two programs were given to us that we had to run, changing various variable, power etc. until the images of the cuts appeared optimum. Again, we had two cameras focused on the workpiece that we initially set up. One optical and one CCTV and both could be viewed on our computer screen. The second program took moved the laser in a snake shape up the workpiece incrementally cutting deeper in variable steps.
Once we had attenuated the power sufficiently that the image appeared optimal, we had to modify the program to cut in all four directions to enable us to compare the results of directional change next week when we measure these cuts. My previous MSc experience came in handy here and I was quickly able to write a new section of code that would achieve this. Again, we had to change variables and power etc. to optimise the laser cuts making it easier for us to measure next week. The dots are where the cut height is changed and the red is the extra program cuts that we added starting at the deepest cut, incrementally raising so that adjacent cuts are the same height for comparison.
This time we finished ahead of time, but instead of heading home we decided to talk Lilly into helping us go through our missed interferometer lab. She kindly agreed but we only had time to get through the third sample before she had to head off home. We can go through our final sample before we start our lab next week.
I think I can speak for the others when I say that we all found this experience very stressful but once we were finished, quite a relief but fulfilling. I feel so much better about this experience this morning following a great sleep. For the past week, my sleep patterns have not been so good because of my excitement and anticipation of this course. I now feel grounded and ready to go. Before I can start though, I really do need to find and buy a car this weekend. Also, it’s the Japanese Grand Prix. Lewis just broke the, “total number of poles” record again which means that he has now won pole position at all the GP’s on this year’s calendar. See you next Tuesday Cambridge!