How a Fresnel Lens works, using a simple blackboard model.

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  • เผยแพร่เมื่อ 31 ต.ค. 2012
  • David shows the construction of a Fresnel Lens, using magnetic sheet on a blackboard

ความคิดเห็น • 234

  • @lambda4931
    @lambda4931 6 ปีที่แล้ว +226

    I’m surprised this doesn’t have a million hits. Fresnel may have been a genius, but your lesson is a close second. Great job !
    Thank you

    • @mad.scientist
      @mad.scientist  6 ปีที่แล้ว +23

      Thank you very much.

    • @qwepoiqazplmzxcmnbqw
      @qwepoiqazplmzxcmnbqw 3 ปีที่แล้ว +6

      As a student your never really see the use for theory (unless it's personally inspiring). However, outside the classroom you may need this information for personal or business endeavors. Your video clearly explains this concept an currently with all the VR developments a lot of people find value in your work. Put simply thanks David, good work and I sort of wish I had you as a teacher growing up.

  • @crunchylumpia
    @crunchylumpia 3 ปีที่แล้ว +133

    this is the best explanation of a fresnel lens ever...

    • @asueft
      @asueft 2 ปีที่แล้ว +3

      Yup

    • @mad.scientist
      @mad.scientist  ปีที่แล้ว +3

      Well thank you

    • @mad.scientist
      @mad.scientist  ปีที่แล้ว +3

      Thanks

    • @neerajwa
      @neerajwa 10 หลายเดือนก่อน +2

      Yes

    • @SpinStar1956
      @SpinStar1956 7 หลายเดือนก่อน

      Have to say after all these years, I can finally understand a Fresnel lens came into existence 😊
      Wow! EXCELLENT explanation 😮
      Thanks❤

  • @tonyhardie7716
    @tonyhardie7716 2 ปีที่แล้ว +2

    Best description of the Fresnel lens I’ve ever seen.

  • @imtiazindia
    @imtiazindia 3 ปีที่แล้ว +58

    Wow!! Is it really that simple? With teachers like these science lectures just become fun. Thank you so much. Sir. 🙏

  • @mm-qd1ho
    @mm-qd1ho 6 หลายเดือนก่อน +2

    Well done! They should demonstrate this at every lighthouse visitor center.

  • @sleethmitchell
    @sleethmitchell 6 หลายเดือนก่อน +3

    been a sailor a long time. finally, i understand the fresnel lens MUCH BETTER! thanks!

  • @ResDog70
    @ResDog70 3 ปีที่แล้ว +37

    In less than 3:40 you have perfectly explained to me what I've been trying to grasp for decades. I've always been fascinated by these lenses and have had an idea of the science behind it, even after reading multiple papers on the subject. Thanks to you, I now have a grasp of the properties involved and no longer just an 'idea'.

  • @retiredpd
    @retiredpd 8 หลายเดือนก่อน

    Every once in a while I find one of these gems that has been out there for a while and this is definitely one of them 👍👍

  • @jaydenwilson9522
    @jaydenwilson9522 6 หลายเดือนก่อน +1

    GREAT TEACHER!
    PERFECT VISUALISATION!

  • @brianmckerrow817
    @brianmckerrow817 6 วันที่ผ่านมา +1

    Now that was teaching comprehension!

  • @chandra_955
    @chandra_955 3 ปีที่แล้ว +17

    This video should've popped up first when I typed "fresnel lens explained". Could've saved lot of my time.

    • @dictionaryofwords1108
      @dictionaryofwords1108 3 ปีที่แล้ว +1

      You're lucky you have a keyboard, I had to find this video with just my mouse and the clicker button

  • @Lew114
    @Lew114 7 หลายเดือนก่อน +1

    Thank you. This has been bugging me for decades!

  • @tonyclifton265
    @tonyclifton265 6 หลายเดือนก่อน +2

    this is brilliant! i've got a degree in physics including optics but never thought of a fresnel lens quite this way

  • @juliamesnikoff7964
    @juliamesnikoff7964 3 หลายเดือนก่อน +1

    Wow, what a terrific explanation! Thank you.

  • @tonydemaria3386
    @tonydemaria3386 7 หลายเดือนก่อน +1

    👍👍👍👍👍 The presentation and explanation of how a fresnel lens is a "work of art".....Bravo!!! 5 Stars, EXCELLENT! and only 218 seconds! 🙏🙏🙏🙏🙏

  • @AlbertaGeek
    @AlbertaGeek 8 หลายเดือนก่อน +1

    I've always wondered. Now I know. Absolutely brilliant.

  • @surfingcuriositywaves4046
    @surfingcuriositywaves4046 11 หลายเดือนก่อน +3

    That's a great and concise illustration of the principles and the application. Thank you for helping clarify the critical understanding.

  • @earlzeller3015
    @earlzeller3015 7 หลายเดือนก่อน +1

    Easily the best demonstration I've seen yet! Well done, sir.

  • @toma5153
    @toma5153 8 หลายเดือนก่อน

    A terrific easily understandable explanation. Thank you.

  • @barryporteous4904
    @barryporteous4904 2 ปีที่แล้ว +7

    Excellent "old school" style with the moving pieces! I hope many more will see and benefit from this succinct demonstration. Thank you.

  • @chrisblenkinsopp8588
    @chrisblenkinsopp8588 7 หลายเดือนก่อน

    Great lecture, have a raise in pay!

  • @Rick_Dunaway
    @Rick_Dunaway ปีที่แล้ว +1

    The best explanation ever! Thank you Sir

  • @shinola228
    @shinola228 7 หลายเดือนก่อน

    Great explanation. And remarkable invention by Mr.Fresnel. I would have been interesting to see how he actually crafted his first lens..

  • @MetalMario137
    @MetalMario137 ปีที่แล้ว +4

    This is such an amazing way of explaining this concept! Thank you so much for this physical representation. One day I'd like to attempt building one to see if I can create a solar-powered blacksmithing forge.

  • @w1swh1
    @w1swh1 7 หลายเดือนก่อน +1

    Brilliant David! Now I know all about a Fresnel lens!! Thank you!!

  • @lothargroschel1414
    @lothargroschel1414 2 ปีที่แล้ว

    Thank you for your nice explanation. I visited a lighthouse in my vacation some days ago.

  • @rrrttt3543
    @rrrttt3543 6 หลายเดือนก่อน

    That was a beautiful explanation, thank you.

  • @vivelemoi
    @vivelemoi 11 หลายเดือนก่อน

    Magnificent in its simplicity. Thank you!

    • @mad.scientist
      @mad.scientist  11 หลายเดือนก่อน

      Glad you like it.

  • @djkasperg
    @djkasperg 7 หลายเดือนก่อน

    Brilliantly explained.

  • @markplain2555
    @markplain2555 7 หลายเดือนก่อน

    That's it?... bloody amazing. How come I never learnt about this in my optics course? I was robbed of a very cool education!! Thanks David.

  • @LightningJackFlash
    @LightningJackFlash ปีที่แล้ว +2

    Great :) Thanks for that, I loved it :)

  • @fridtjovruden5225
    @fridtjovruden5225 7 หลายเดือนก่อน +1

    This is just pure unadulterated intellectual educational elegance. Do not find better words. Awesome experience to watch this. Thank you professor 🙂

  • @Luachair
    @Luachair 7 หลายเดือนก่อน

    Best vid of its kind that I have ever seen! Marvellous, congrats, everything. I have double vision but my optical consultant has access to plastic Fresnels that he can stick on to my specs, he determined what power to use and bingo! double vision corrected!

    • @mad.scientist
      @mad.scientist  7 หลายเดือนก่อน

      Thank you, I’m glad things went well with the specs.

  • @TheFlyingVyse
    @TheFlyingVyse ปีที่แล้ว

    Best example!! Thank you so much

  • @elmoreglidingclub3030
    @elmoreglidingclub3030 6 หลายเดือนก่อน +1

    Brilliant!! Never knew this but what an awesome explanation. Thank you for sharing your knowledge in such a compelling way.

  • @jimeagle5483
    @jimeagle5483 7 หลายเดือนก่อน

    Phenomenal lesson. Thank you.

  • @kalakalatu
    @kalakalatu 3 ปีที่แล้ว +4

    Brilliant!! So simple and concise that even I understand it now.

  • @GlynisDance
    @GlynisDance 2 ปีที่แล้ว +1

    Thank you. A very clear explanation - you obviously put some thought (and ingenuity) into it!

  • @renatorochamiranda
    @renatorochamiranda 3 ปีที่แล้ว

    Nothing is more creative than knowledge. Congratulations! I will share it on my blog!

  • @michaelgoldmann3734
    @michaelgoldmann3734 8 ปีที่แล้ว +12

    great video David :)
    you helped me a lot in my physics presentation at school and the class was so enthusiastic and listened through this, otherwise pretty boring, topic of lenses ^^

  • @Desperado202
    @Desperado202 2 ปีที่แล้ว

    WOW what an interesting explanation!

  • @Cambeast123
    @Cambeast123 2 ปีที่แล้ว +1

    That was a wonderful visual explanation, thank you. The definition of concise.

  • @bananian
    @bananian 2 ปีที่แล้ว

    Wow, that makes so much sense.

  • @bm_videa
    @bm_videa 2 ปีที่แล้ว +2

    Great presentation! Highly educational and easy to understand new knowledge. You really have the teacher‘s gift.

  • @kotak1858
    @kotak1858 2 ปีที่แล้ว

    wow wow ..... its super video.... sir you know very well how to teach .... its realllllllly super

  • @jungleb
    @jungleb 3 ปีที่แล้ว

    Awesome video, awesome comments. Congrats

  • @mad.scientist
    @mad.scientist  3 ปีที่แล้ว +11

    Thank you.

  • @mwangijameswamae6169
    @mwangijameswamae6169 2 ปีที่แล้ว

    I loved this explanation, both the verbal and the neat visuals. I have been trying to figure out Fresnel lenses for a minute, this was an "aha" moment. Thank you...

  • @mattgazewood
    @mattgazewood 5 ปีที่แล้ว +7

    thank you I've been looking for this type video for so long perfectly explained

  • @mauricioalbertoaguirresoto3505
    @mauricioalbertoaguirresoto3505 ปีที่แล้ว

    Woah!!!!!!!! NO WORDS!! AWESOME!! USEFUL!!

  • @carlfink5409
    @carlfink5409 3 ปีที่แล้ว +1

    Well done! I am trying to understand how a bifocal and trifocal inter ocular lens (IOL)-used for cataract surgery lens replacement-works. A Fresnel lens is at the heart of the technology. This explanation is so clear and just what I was looking for. Thank you so much!

    • @mad.scientist
      @mad.scientist  3 ปีที่แล้ว +1

      Thank you, you are more than welcome.

  • @ShuvraKundu
    @ShuvraKundu 3 ปีที่แล้ว

    One of the best physics of stuff video on internet ever!

  • @HankW
    @HankW 3 ปีที่แล้ว +1

    What a nice explanation!

  • @jamesallen74
    @jamesallen74 3 ปีที่แล้ว +1

    Fantastic explanation. Very very easy to follow.

  • @Kargoneth
    @Kargoneth 3 ปีที่แล้ว +1

    Short and intuitive. I love it.

  • @blacklabel6223
    @blacklabel6223 2 ปีที่แล้ว +1

    Thank you! I’m in the middle of designing a product for a hobby and this was super super useful in actually knowing what lense I would need in terms of someone who’s never dealt in optics before

    • @mad.scientist
      @mad.scientist  2 ปีที่แล้ว +1

      Glad to be useful, I would like to know more about your product.

    • @blacklabel6223
      @blacklabel6223 2 ปีที่แล้ว +2

      @@mad.scientist it’s a solar engraver for some local Amish folks looking to wood burn large tables. Putting a fresnel lense on a gimble with a low friction base it can be set on the table, adjusted for focus, then just slid around to engrave an image. Drawing it with pencil first helps it burn much faster from what I’ve seen too.

  • @uptown1_photography949
    @uptown1_photography949 ปีที่แล้ว

    Excellent explanation!

    • @mad.scientist
      @mad.scientist  ปีที่แล้ว

      Glad you think so! Cheers, David

  • @meetoptics
    @meetoptics 2 ปีที่แล้ว +3

    Congratulations for this short and amazing explanationon how fresnel lenses work. This platform let us spread all we know and from MEETOPTICS we are proud to be part of the photonics community and to help engineers and researchers in their search for optical lenses through our site, from prisms to mirrors and fresnel lenses.

  • @samsmith9764
    @samsmith9764 3 ปีที่แล้ว +2

    Awesome explainations, cheers

  • @muddymudskipr
    @muddymudskipr 3 ปีที่แล้ว

    Taken em to SCHOOL!!!!!!!!!!! Loved it;)

  • @EG-cs3wv
    @EG-cs3wv 3 ปีที่แล้ว +2

    Amazing and simple to follow lesson. Very well explained! Thanks

  • @halonothing1
    @halonothing1 11 หลายเดือนก่อน +1

    I thought a while ago about how you could make a flat lens by stacking specifically shaped layers of materials gradually larger/smaller refractive indices, so as to create a gradient without needing a lens. Then I found out, it's already been thought of and is being looked into. I didn't realize how similarly fresnel lenses work, compared to this concept as well.

  • @Frejjan
    @Frejjan 10 หลายเดือนก่อน

    Great video! Thanks a lot

  • @MacsMachines
    @MacsMachines ปีที่แล้ว

    Wow what a teacher!! 👍👍

  • @theclownofclowns
    @theclownofclowns 2 ปีที่แล้ว

    Awesome video! Made me understand it completely in just 3 minutes

  • @aishwaryadevbanerjee6037
    @aishwaryadevbanerjee6037 2 ปีที่แล้ว

    Simply one of the best and most beautiful explanations.

  • @ulaB
    @ulaB 3 ปีที่แล้ว

    Things I didn't even knew I wanted to know... Very well explained.

  • @njgjhrjd
    @njgjhrjd 2 ปีที่แล้ว +1

    Well, I’m sure I’ll need this information one day (why would TH-cam recommend this otherwise, right?) With crystal clear explanation like this I don’t think I’ll ever forget how it’s made :) So thank you!

  • @totoro5356
    @totoro5356 3 ปีที่แล้ว

    Thank you so much for sharing.

  • @iamcmac
    @iamcmac 3 ปีที่แล้ว

    This so eloquently explained. Thank you.

  • @ocensored3893
    @ocensored3893 2 หลายเดือนก่อน

    wow, really impressive

  • @pepetrueno6012
    @pepetrueno6012 4 หลายเดือนก่อน +2

    Excelent 😮

  • @moeshickenyay
    @moeshickenyay 3 ปีที่แล้ว

    Use them all the time, never understood how they work, excellent and simple explanation, Thanks.

  • @akosial
    @akosial 3 ปีที่แล้ว +1

    Thank you for the time and effort you put into making this! Very well explained!

    • @mad.scientist
      @mad.scientist  3 ปีที่แล้ว +1

      Glad you liked it, thank you.

  • @conchosewing
    @conchosewing ปีที่แล้ว

    very well explained. thank you!

  • @itzkatsawayo
    @itzkatsawayo ปีที่แล้ว

    Well done. Thanks.

  • @AveryDelMiller
    @AveryDelMiller ปีที่แล้ว

    Woww! This is a great explanation!!!

  • @JamesWitte
    @JamesWitte 2 ปีที่แล้ว

    Thanks for this brother. You're an amazing educator

  • @gokulchandran5586
    @gokulchandran5586 8 หลายเดือนก่อน

    well explained, thank you.

  • @testimony-
    @testimony- 2 ปีที่แล้ว

    Perfect example!

  • @basimbaig
    @basimbaig 3 ปีที่แล้ว +1

    What an absolutely amazing explanation!

  • @sleepygrumpy
    @sleepygrumpy ปีที่แล้ว

    You absolutely nailed this concept this is such an impressive video

    • @mad.scientist
      @mad.scientist  ปีที่แล้ว +2

      Thank you. Sleepy and grumpy? I’m guessing that, like me, you follow politics too😊

  • @sahil-pu3cc
    @sahil-pu3cc 2 ปีที่แล้ว

    Really nice explanation

  • @implespaynter
    @implespaynter 2 ปีที่แล้ว

    WOW! that was amazing!

  • @nithikasandinu5843
    @nithikasandinu5843 2 ปีที่แล้ว

    The best explanation ever. Valid forever 😎⚡

  • @UsamaSiddiqui1
    @UsamaSiddiqui1 2 ปีที่แล้ว

    Simply amazing. Thank you

  • @Tjalve70
    @Tjalve70 6 หลายเดือนก่อน

    He's right.
    The lens is definitely cool.

  • @marpekriram103
    @marpekriram103 5 ปีที่แล้ว

    cleared the concept in a very lucid manner.... thumbs up

  • @eurekayoung2537
    @eurekayoung2537 4 ปีที่แล้ว +1

    Very intuitive! Thank you!

  • @PatrickSalisMEDIA
    @PatrickSalisMEDIA 3 ปีที่แล้ว

    excellent demonstration... the best ... thank you.

  • @noxix7641
    @noxix7641 3 ปีที่แล้ว

    I'm making some of these now, fantastic explanation.

  • @luciensims
    @luciensims 3 ปีที่แล้ว

    Brilliant explanation, thanks

  • @cadfael4598
    @cadfael4598 7 หลายเดือนก่อน

    Thanks. That was great

  • @rogeromega5
    @rogeromega5 3 ปีที่แล้ว

    Thank you so much. I have been reading trying to figure out from equations but this is a wonderful explanation. Thanks

  • @odal6770
    @odal6770 3 ปีที่แล้ว

    beautifully done!

  • @hv1461
    @hv1461 3 ปีที่แล้ว

    Great explanation, thanks.

  • @ivuldivul
    @ivuldivul 3 ปีที่แล้ว

    Perfectly clear!

  • @Ivan_StandWithUkraine
    @Ivan_StandWithUkraine 4 ปีที่แล้ว

    Thanks for the explanation.

  • @ThomasHaberkorn
    @ThomasHaberkorn 6 ปีที่แล้ว +2

    wow great presentation

  • @lars5458
    @lars5458 3 ปีที่แล้ว

    This is genuinely interesting, even though I have nothing to do with Lenses what so ever.