define your love life

Optical Materials, Neyts, K. et. al., p.45.

i got more than a sentence, i have a freaking image! hahaha. so to sum up my 1000 words i suppose one interpretation could be that my love life is non-existent? sheesh, that's depressing. but, wait, there's more! forget silicon, i could be germanium! which means i have the possibility of actually having a love life when strained significantly? but what if i don't want to be strained? :( or, or we could add dopants to lower the gamma valley. what does that even mean, like, introduce third parties to the relationship? this is ridiculous! i don't wanna shaaaare :)) either that sucks equally well or that just goes to show one should NOT take dating advice from engineering text books :)) 

this is funny, stuff like this should go viral haha. it's like taking horoscope to a whole new level - fortune telling by band diagrams. HAHAHAHA 

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ang huling el bimbo (eraserheads)

Soundcloud: Ang Huling El Bimbo (Eraserheads) - Piano Accompaniment

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missing piece revisited

(in progress. dear self, your handwritten, unedited, and perfectly incoherent "masterpiece" is lost somewhere in a pile of books and course notes. sorry. give me until the end of september to sort things out.)

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long drive

drive → laag with no particular destination in mind → buntings → fiesta → lechoooooon

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delusion

there are two videos i can hardly bring myself to look at again. one was the embarrassing video of a poorly choreographed graduation dance presentation and the other is my department's entry to the the 2008 csm week film competition. we were juniors that time and it was directed by my batch mate and most of the cast were from my batch as well. it actually has an interesting story line if one could piece the frames together but there is just something ridiculously funny about seeing your friends, whom you've joked and laughed and fooled around with for a good three years, try to act in a drama. i mean, i just can't take them seriously i couldn't watch a scene without laughing my head off :)) and i believe the ONLY time i've seen it from intro to credits was when sandy showed it to me before submitting it to the committee. i remember i wasn't able to watch the screening because we had a game against bio the afternoon it was screened.

my wardrobe was hideous! i mean, the skirt was a little too long but okay, the t-shirt was weird, but the bag was totally hideous :)) and the hair! ugh! couldn't we have put it down or at least put it up in a proper pony tail? i'm so embarrassed with myself haha.

but at least i get to hear karl's piano composition again even though it was poorly recorded and not mentioned in the credits. it was, i believe, called "sunflower" and karl would play it in the octava's grand piano while passing the time until our next class.

somehow i remembered the film today after talking with frankie so i downloaded it from his playlist for the sake of having my own copy even if i couldn't watch it properly haha.

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musescore!

look what i have just discovered - MuseScore - very good software for writing sheet music - and it's free! i had a similar software once but it didn't have templates and it was a trial version so one could only do a few files and you couldn't do much with it except the most basic things.

i came upon the software because jeddo was looking for sheet music for the song come back home by 片平里奈. since i couldn't find one (and wasn't expecting to considering the song came out only late last year and she's a new artist) i decided writing one would make a good pastime. i worked with what i had for a few minutes, which was a one octave digital keyboard on my phone, which, i assure you, is downright annoying and trying to work with. not to mention one has to write down the notes by hand and have to draw the measures manually. gah.

here's what i've done so far and i think it's quite a good start hihi. the software's really nice, i can do playbacks, set the tempo, export to midi or pdf or png, add all those exotic notations, etc..it's simply fun to work with :) i'm transcribing it for the flute but i added the bass anyway because it sounds better during playback haha. aaand apparently jeddo's flute cannot play anything lower than B3 so i'll have to transpose it at the end, which is a no-brainer because the software has this functionality! cool.

Come_Back_Home_-_片平里菜
Soundcloud: Come_Back_Home_-_片平里菜 - flute
[sheet music updated: 15/07/14]

why didn't i discover you sooner?

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big dogs and bookshops

rue keyenveld 48, ixelles, brussels.

little heaven <3

OLD books everywhere!

i hope old, hard bound books like these would find their way into my own library someday.

avoc and the kind grandpa who allowed me to play with avoc :)

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optical design with ray tracing

Q1. describe how you would define the following structure on ASAP. in addition, create an ASAP script which generates the surface, the only necessary condition being n1 != n2.

A1. the provided volume could be defined using 5 surfaces: elliptical air-n1 interface, tubular air-n1 interface, elliptical n1-n2 interface, tubular air-n2 interface, and elliptical air-n2 interface. the material composition is defined by defining a database of material parameters, particularly the refractive index. the INTERFACE command is necessary to define not only the material refractive index but the reflection, transmission, and absorption properties as well.

then    
SYSTEM NEW
RESET
UNITS MM
MISSED 0.5
WAVELENGTH 1550 NM
SPLIT 1
 
MEDIA
  1.4 'N1'

MEDIA
  1.5 'N2'
DIA=2
L1=2
L2=2
!! Grin substrate
SURFACE                              
  PLANE Z 0 ELLIPSE (DIA/2) (DIA/2)
OBJECT 'N1.EDGE'              
INTERFACE 0 1 N1 AIR
SURFACE                                                
  TUBE Z 0 (DIA/2) (DIA/2) (L1) (DIA/2) (DIA/2) 0
OBJECT 'N1.TUBE'      
INTERFACE 0 1 N1 AIR
             
SURFACE                              
  PLANE Z (L1) ELLIPSE (DIA/2) (DIA/2)
OBJECT 'N1N2INTERFACE'              
INTERFACE 0 1 N1 N2
SURFACE                                                
  TUBE Z (L1) (DIA/2) (DIA/2) (L1+L2) (DIA/2) (DIA/2) 0
OBJECT 'N2.TUBE'      
INTERFACE 0 1 N2 AIR
 
SURFACE                              
  PLANE Z (L1+L2) ELLIPSE (DIA/2)
OBJECT 'N2.EDGE'              
    INTERFACE 0 1 N2 AIR

!! DETECTOR
SURFACE
PLANE Z (L1+L2+1) 0 ELLIPSE 2@((DIA)/2)
OBJECT 'DETECTOR'

                   
!!SOURCE
WINDOW Y Z
PLOT FACETS OVERLAY
EMITTING DISK Z 0 -(DIA/2) (DIA/2) 100 5 5
!!SOURCE DIR 0 0 1
FLUX TOTAL 100

TRACE PLOT
CONSIDER ONLY DETECTOR
WINDOW  X Y        
!!SPOTS POS
!!PLOT FACETS OVERLAY
!!STATS
$VIEW

Q2. (a script for a light pipe is provided) what is the intensity at the output of the light pipe? calculate the etendue at the entrance and end facets of the light pipe.

A1. the etendue is a pure geometric concept that does not say anything about the energy distribution of the light but determines the positional and angular extent of a bundle of light. it is important for calculating how much light can be coupled from a source to a detector theoretically. the etendue is a  function of the refractive index, detector/emitter area, as well as the acceptance/exit solid angle. the light pipe exit angle could be extracted from the simulation by using the ANGLES command.

then
SYSTEM NEW
RESET  
UNITS MM 'WATT'
MEDIA
  1.48 'ACRYLIC'    

PIXELS 101
SPLIT 1 MONTECARLO
FRESNEL AVE

SURFACE
  PLANE Z 0 ELLIPSE 1 1
OBJECT 'FACE_ENTRANCE'
INTERFACE COATING BARE_SUBSTRATE AIR ACRYLIC        
SURFACE
  TUBE Z 0 1 1 10 2 2 0 0
OBJECT 'TUBE'
INTERFACE COATING BARE_SUBSTRATE AIR ACRYLIC

SURFACE
  PLANE Z 10 ELLIPSE 2 2
OBJECT 'FACE_EXIT'
INTERFACE COATING BARE_SUBSTRATE AIR ACRYLIC

EMITTING DISK Z -0.01 1 1 500000 90 90          
FLUX TOTAL 100
WINDOW Y Z
PROFILES OVERLAY
TRACE PLOT 10000

!!TRINIDAD START
PIXELS 101
WINDOW X Y
CONSIDER ONLY FACE_EXIT
!!SELECT ONLY COS[25] C
SPOTS DIR 

STATS
DISPLAY
  ANGLES
  PICTURE
RETURN
!!TRINIDAD END
$VIEW

Q3. (this question was about a comparison of the simulation time between SPLIT and SPLIT MONTECARLO commands using the light pipe scripts previously provided) which simulation model would you use for optimization?

A1. (add $TIC command to script to get quantitative values of the simulation time) the SPLIT command would generate much more rays than the SPLIT MONTECARLO because it could generate more than one child rays with power distributions according to INTERFACE and MATERIAL settings. SPLIT MONTECARLO, on the other hand, generates only the child ray with the highest probability of occurrence and in fact conserves the number of rays created within the simulation. this being the case, it also follows that SPLIT MONTECARLO simulations are faster than normal SPLIT commands. for design and optimization of light pipes, since we are only interested in getting a homogeneous distribution of light at the output, using SPLIT MONTECARLO would be acceptable since it's faster and gives us the information we need, anyway. on the other hand for ghost analysis, for example, one should use the SPLIT command in order to study where unwanted rays could come from or arrive on your detector.

Q4. describe how you would design an hot mirror. no need to write a script.

A1. a hot mirror is a reflective filter, composed of layers of dielectric materials, which reflects IR light (around 750-1200 nm) and allows visible light to pass. as a starting point we can first define a low-pass filter with central wavelength around 750nm or so. this generates not a perfect low pass filter but some sort of a band pass filter with a bandwidth of about 200nm. since the range of visible light is larger (380-750nm) we need to increase the bandwidth to allow all visible light to pass. this can be done by adding another set of layers of dielectric material to create low pass filters centered on the wavelengths you wish to suppress. ripples in the spectrum may be smoothed out by optimizing the widths of the quarter-wave plates. furthermore, hot mirrors are extremely sensitive to the incident angle of light. in order to account for this sensitivity in the design (and minimize it as much as possible), one may use materials of higher refractive index.

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asap

just some cool stuff one can do with ASAP:

Dove Prism

POFcoupler1_Shao_Trinidad

POFcoupler2_Shao_Trinidad

Free-form TIR reflector_Shao_Trinidad

Tapered Light Pipe

view from the light sources (4 LEDs) and the homogeneous distribution of light at the tapered end.

Projector_Shao_Trinidad

GhostAnalysis

LCD Diffuser Design

and a lot of cooler ones like modeling interference..by ray tracing!

MICHELSON_INTERFEROMETER

SLITDIFFPATTERN

ProjectionEngine_Pro6_Shao_Trinidad

red (bottom), green (left), and blue (top) light sources focused on a polarizing beam splitter designed to transmit s-polarized light.

very good homogeneity of red, green, and blue light at the detector.

SELFOC

see the parabolic bending of light in the lens? beautiful! boyang did ask why we had to let the light propagate in free space instead of just using one GRIN lens to couple light into two fibers and i was, like, so we'd have something to optimize, of course! haha. indeed, using just one lens would be very advantageous as you can get rid of some of the alignment issues, for one. seriously, though, things like these actually exist in the market but they've fixed the alignment pretty well.

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i think i'm drunk haha

prof. gunther was around for a while in the morning. andreas was also around for the whole day but apparently he has a girlfriend. tsktsk. i'm still allowed to like him, though, yes? but that's not why i'm drunk. haha.

we had a mini joyride with floris to het pand where the gala dinner was held. and since we arrived 30 minutes early, he treated us to a beer at his friend's bar. so we lounged for a while with satadal in front of the leiss river and just enjoyed the wonderful gent afternoon. we've been enjoying a very good weather for the duration of the summer school and i hope it will still be as good tomorrow.

anyway, floris bought us beer and apparently he suggested one with relatively high alcohol content for me. i couldn't even remember the name. during dinner they served wine then another wine then champagne. haha. soooo i think i'm..maybe not exactly drunk..tipsy. and now it's 11pm and i still need to get back to brussels and wake up early tomorrow to catch the train back here to gent. haha. i can HARDLY wait for this week to end and i am TERRIBLY tired. goodness!

i was at a table with a group of friends, some phd students and gordon, from some company in the UK, and we talked about culture and research and industry trends and how to differentiate wines and a lot of other stuff. xinyu asked about my plans after masteral and when i mentioned i'm also considering getting a phd, he was pretty surprised and said - but phd takes a long time and a lot of effort, shouldn't you get married first? hahahahahahaha. yeah thanks for the concern, but i should get a boyfriend first, though, haha.

but then again, according to him apparently a lot of the chinese phd students here found me really pretty compared to filipino celebrities, take note - celebrities, haha which is reaaaally surprising hahaha, so that's good news i suppose hahahah.

i laugh too much..i must be really tipsy..

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here we go again

お久しぶり <3

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