Week 7: Summer Placement

Day 1

The group meeting was cancelled this morning as my supervisor was busy with lots of meetings with the IFE (Inertial Fusion Energy) Network and CIFS (Centre for Inertial Fusion Studies). So instead I took this opportunity to clean up my lab space - it was so lovely to be back in the lab! I missed it so much. I then plotted all the data I had collected from my previous measurements of the spectra of a white light source passing through different optics - I had 22 graphs by the end of the day!

Clear skies

Sunny day

Plotted graphs

Treat from a PhD student :) mmmm...

My lab workspace 

 Day 2

My supervisor was very busy with the IFE Network conference and I couldn't meet him today - so instead I took the opportunity to have a science-y morning at the Science Museum. As Imperial College student I and a friend got to watch an IMAX film for free - we choseso I went with a friend to watch Robots 3D. It was so inspiring to see the work of scientists paying off to create incredible robots! My favourite was the robot that could catch balls almost as well as a human! The 3D effect was AMAZING! I've never experienced such a great 3D effect.

FUN FACT: The height of the IMAX screen is the size of four double-decker buses!!

It would be one of the most brilliant things if I could build something that everyone could use or  something that would increase the quality of life - maybe a career in bioengineering or a similar field would be something right up my street or even yours. Don't limit yourself to common career paths like medicine, law or dentistry - there are lots of exciting careers out there for you to consider and one of the is perfect for you!

If you are looking for a fun, science-y weekend then check out the science museum. The new cosmonauts exhibition is opening soon so don't miss out!

I got back into the lab in the afternoon and labeled my graphs with a description of the optic in question - such as orange with green tint. I also found some cool optics on the way - one of them looked like a standard mirror but when I looked through it it was like a red filter! See pictures below:

The lights without looking through an optic

Seeing red through the Al-mirror-looking optic

Seeing red

The Al-mirror-looking optic

Seeing purple through an Al mirror-looking optic

Looks like an Al mirror

Iris

The different optical pieces I worked with

One of the optics I characterised

Part of another experiment in the lab I was working with which I thought looked quite artistic

3D glasses

Cravings exhibition in Science Museum

Science Museum

Day 3

The group meeting this morning was very inspirational. I've missed so much science in the month that I was away! One of the PhD students had a sleepless night because of physics - he thought of a way to get rid of back scatter from a laser system. His supervisor was amazed and so, I too, was in awe - it was such a cool moment, the room went quiet as he spoke his intellectual mind. I couldn't have asked for a better return to the group. New experiments were underway and there was a lot of collaboration. After the meeting I worked with a PhD student to order the parts for the popomatic - this meant taking the popomatic down to the lab and taking it apart so we could identify the parts. :) After this, we had some lunch as a group and it was nice to be with the group again. We got back into the lab and the PhD student quickly identified the basic parts such as the cage you see in the popomatic, the posts, post-holders, lens mounts and other related objects. The lenses were cleaned using the drag method, I mentioned in a previous post, and we found that they weren't labeled so we had to find the focal lengths of the lenses ourselves in the only way we know - an experiment. In order to do this we needed to set up a collimated light beam (light that is in the same direction and all parallel to each other). I used my previous set up that I characterised optics with to set up a collimated white light beam but there was a lot of chromatic aberration (separation of different wavelengths) due to the spherical lens I was using to collimate the beam. Instead the PhD student set up a system which expanded a laser beam and then collimated it to a larger beam diameter. A waveplate and calcite cube was used in the system which were pieces of equipment I had learnt in my second year of undergraduate studies - it was so nice to relate what I had learnt to what I was doing in the lab! After having made the collimated laser beam of larger diameter, we put the optics in and measured the focal length (the distance from the centre of the lens to the point where the diameter of the laser/light beam is the smallest). We found that the lenses were planoconvex lenses (shaped like a half moon) with focal lengths of 15 and 20 cm. We found these lenses on Thorlabs (supplier of optical equipment) and I then put the part numbers, price and quantities of each item we wanted to purchase in a spreadsheet so that I could get a feel for the overall price. We found lots of aluminium optical rails that I could use as the backbone of the popomatic but needed to find out the names of the screws that we needed to mount the optics to the rail. This was a task for tomorrow.

The current version of the popomatic

Cage mount from the popomatic

Finding the lenses I need and putting the part details in a spreadsheet

My lab work space

The laser system I used to find the focal lengths of the lenses

Birefringent material

Waveplate - linearly polarises the light

Calcite cube

Finding the names of all the screws I needed was a bit of a challenge but a great learning experience

Day 4 and 5

Turns out the aluminium optical rail was too small for the popomatic so instead I found a thicker one on RS Components, a leading distributor of electronics, electrical and industrial components, and so ordered it from here. The PhD students were always willing to help me with part names and other questions I had. I am ever so grateful for their help. I continued with searching for the parts I needed for the four popomatics I shall be building in the coming weeks. I split the parts list into optics, housing and electronics and sent them to my supervisor for him to order them. I also got in contact with The Plastic Shop to get a quote for the housing for the popomatic, a plastic tube. Who knew it would cost £150 for a 1 m tube of acrylic! Over the weekend I plan to send my CAD drawings to another company recommended by my supervisor in order to get a quote for the acrylic tubes I need.

Aluminium profile I require but couldn't find a larger size at the time

Add caption

Finding the parts I need

Quick drawing of the slit in the popomatic casing (where balloons are inserted) - to be sent to companies for a quote on pricing for an acrylic tube with the slit cut

ABS box - electronics kept inside

Key switch for popomatic 

A lovely view of London from Imperial's Physics Department (Level 10)

The weather was great on Thursday so I shall end this blog with a lovely picture of the sunset I saw in Hyde Park after a game of frisbee with friends after work. Enjoy your weekend!

Hyde Park sunset

Sunset outside Physics Department

Lovely weather - clear skies