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 Author Topic: Ejs open source converging & diverging Lens object image high school java applet  (Read 62628 times) 0 Members and 1 Guest are viewing this topic. Click to toggle author information(expand message area).
lookang
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 « Embed this message on: June 21, 2009, 10:09:01 pm » posted from:Singapore,,Singapore

Ejs open source converging & diverging thin convex Lens object image high school java applet
now able to allow for inquiry learning of
Under topic of optics let see google will tag the new key word " optics " " lens simulation "
physics Images formed by a converging lens object distance equal f
physics Images formed by a converging lens object distance greater than 2 focus length
physics Images formed by a converging lens object distance lesser than f
physics Images formed by a converging lens object distance equal to 2 focus length
physics Images formed by a converging lens object distance between f and 2f
reference:
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=704
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=48 Thin Lens (converging/diverging lens) no mirror
to become
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1140.0
trying to make it more customized for K12 physics, the physlet len applet is superb, i doubt i can make the Ejs version better.just trying to learn how to make this from tinkering your codes and other meaningful stuff
cited by http://en.wikipedia.org/wiki/Lens_%28optics%29

Embed a running copy of this simulation

Embed a running copy link(show simulation in a popuped window)
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• Please feel free to post your ideas about how to use the simulation for better teaching and learning.
• Post questions to be asked to help students to think, to explore.
• Upload worksheets as attached files to share with more users.
Let's work together. We can help more users understand physics conceptually and enjoy the fun of learning physics!
 Lens object image java applet.PNG (68.71 KB, 1024x768 - viewed 1714 times.) *** There are 4 more attached files. You need to login to acces it! « Last Edit: October 01, 2012, 04:36:59 pm by lookang » Logged
lookang
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 « Embed this message Reply #1 on: June 28, 2009, 05:19:20 pm » posted from:Singapore,,Singapore

Exercises: designed by lookang

1. Explore the simulation. Notice that you can move the sliders to vary the distance of the object to the centre of the thin len. What do each of the buttons and sliders do?
2. Take about 10 minutes to inquiry through the simulation model and describe the action of a thin converging lens on a beam of light. ( this simulation currently does not have beam of light)
3. Discuss with your lab partner what is the meaning of the focal length f.
* hint: in terms of the way the light rays from the object is bend and pass through where?
4. check the principal rays radio button. Discuss and formulate ideas how the ray diagram allows the drawing of ray diagrams to illustrate the formation of real and virtual images of an object by a
thin converging lens.
* What does the green ray light always do?
* What does the red ray light always do?
* What does the teal ray light always do?
o hint: in terms of the way ray light traveling parallel to and passing through where etc?
5. What does the term linear magnification mean in this simulation.
* Discuss how it is calculated from?
* How many ways are there to determine the magnification of the think converging len.
6. Check the no ray radio button. move the sliders a suitable position of your choice. Now, sketch as accurately as possible on a piece of paper, the principal ray diagram ( minimum 2 rays) to get the image position and height. Practice a few times with different and varied examples to allow you to draw scale diagrams to deduce the focal length needed for particular values of magnification (converging lens only)
7. explore the simulation to make observations of the use of a single converging lens as a
* magnifying glass a
* projector
8. Draw rays of examples for each case to show clearly how each forms an image

Designed by Fu-Kwun Hwang http://www.phy.ntnu.edu.tw/ntnujava/ remixed by welookang@gmail.com for K12 physics "Thin Converging Lens Ray Diagram"

reference: http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=704 hosted: http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1155.0

Ejs open source converging & diverging thin convex Lens object image high school java applet. now able to allow for inquiry learning of
physics Images formed by a converging lens object distance equal f
physics Images formed by a converging lens object distance greater than 2 focus length
physics Images formed by a converging lens object distance lesser than f
physics Images formed by a converging lens object distance equal to 2 focus length
physics Images formed by a converging lens object distance between f and 2f

This thin lens ray diagram java applet has:

Main view:
Lens that is controllable by the focal length f, +f imply converging lens -f imply diverging lens.
Focal points drag-able, 2F, F, F & 2F
u is position of Object from lens center c
v is position of Image from lens center c.
The object is drag-able to the right side of the lens

Top View:
dynamically display a possible use of the lens under different conditions with pictures shared under creative commons licenses and other similar pro usage licenses under attribution.

Bottom View:
4 radio buttons: allows for different visualization purposes of light path in the context of lens
no ray
principal ray
marginal ray
all ray

4 check boxes:
"Real/Virtual?"
"Inverted/Upright?"
"Magnify/Diminish?"
"Same/Opposite side"

Autoscale: to allow visualization view of images formed outside designed screen view.

3 slider control:
u, object distance from c
h, height of object
f, focal length of lens

3 values display:
v, image distance from c
ih, image height
M, Magnification

PHYSICS
(Syllabus 9246)
http://www.seab.gov.sg/SEAB/aLevel/syllabus/2009_GCE_A_Level_Syllabuses/9246_2009.pdf

distinguish between converging and diverging lenses and show an understanding of the
significance of focal length.

5056 PHYSICS O LEVEL (2009)
http://www.seab.gov.sg/SEAB/oLevel/syllabus/2009_GCE_O_Level_Syllabuses/5056_2009.pdf
(i) describe the action of a thin converging lens on a beam of light
(j) define the term focal length
(k) *draw ray diagrams to illustrate the formation of real and virtual images of an object by a
thin converging lens
(l) define the term linear magnification
(m) *draw scale diagrams to deduce the focal length needed for particular values of
magnification (converging lens only)
(n) describe the use of a single lens as a magnifying glass and in a projector and draw ray
diagrams to show how each forms an image
 « Last Edit: January 01, 2010, 04:22:07 pm by lookang » Logged
lookang
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 « Embed this message Reply #2 on: July 13, 2009, 06:52:50 am » posted from:Singapore,,Singapore

1. added lines for the light 3 paths for principal rays different colors and arrow heads.
2. added transparent 100 lines to guide visualization
3. added mechanism for lens changing thickness for converge and concave
4. change color scheme to be more like physlets
5. added pictorial and logic for more scaffolds to help people associate the use of the converging lens
6. limited the height of object to height of lens for closer approximation of image possible
7. added 2F F F 2F and the drag-able 4 points
8. redesign the code for the appearance of pictures to follow Boolean logic
9. added the side/opposite of object and image to follow 4 checkbox
10. debug the appearance of strange lines when p = 1.8 instead of 1.8000000000000001 and f also.
12. added all rays that assume the lens is infinitely long because i can't create the logic for bend or don't bend light
13. background color back to grey, darkgrey causes some visual cursor difficulties to visualize
14. added screen but it does do much except allow some ease of noticing non focus light
july26
15. changed to fit typical pen and paper questions < 40 cm instead of 2 cm
16. improved the lens color to grey convex and concave types
17. background to

"http://www.entre-propel.com/ March 31st, 2009 By Matt Thomas Attribution-Noncommercial-No Derivative Works 3.0 United States"

"http://commons.wikimedia.org/wiki/File:Canon_ir2270.jpg Taken by Fir0002 under GNU Free Documentation License"

"http://www.freefoto.com/preview/02-08-8?ffid=02-08-8&k=Telescope by Photographer: Ian Britton For unrestricted use."

Polaroid Land Camera 360, circa 1969-1971. Photo by the uploader (User:Morven), released under the GFDL and Creative Commons Attribution Share-Alike, version 2.5 or earlier.

"http://commons.wikimedia.org/wiki/File:Magnifying_glass.jpg This is the creation of Tomomarusan"

 spotlight.jpg (1.28 KB, 133x85 - viewed 3904 times.)  80px-Canon_ir2270.jpg (3.56 KB, 80x120 - viewed 3860 times.)  telescopes.jpg (2.21 KB, 125x83 - viewed 3824 times.)  120px-Polaroid_Land_Camera_360.jpg (12.5 KB, 120x109 - viewed 3944 times.)  76px-Magnifying_glass.jpg (1.67 KB, 76x120 - viewed 3899 times.)  overheadprojector.jpg (3.32 KB, 113x150 - viewed 3938 times.) « Last Edit: September 26, 2009, 02:01:44 pm by lookang » Logged
lookang
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 « Embed this message Reply #3 on: July 14, 2009, 11:16:18 am » posted from:SINGAPORE,SINGAPORE,SINGAPORE

found a similar one here
http://www.crescent.edu.sg/crezsphere/applets/Physics/Applets/Light.htm
no picture here since it seems to belong to a commercial entity,

Likes:
2F , F , F , 2F markings
drawing of eyes during magnifying glass

the one made in Ejs at first post is open source and improve-able by others, sure to be great!

made the changes for 2F , F , F , 2F markings
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Fu-Kwun Hwang
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 « Embed this message Reply #4 on: July 14, 2009, 09:22:22 pm » posted from:Taipei,T\'ai-pei,Taiwan

The above web page include two animation: refraction/reflection and thin lens refraction.
However, for the refraction/reflection part. I would suggest you to check out Intensity of reflected s-wave/p-wave.

When light enter into another media, reflection will always occurs.
The animation only show either reflection or refraction. It might introduce mis-concept about the light.
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lookang
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 « Embed this message Reply #5 on: July 14, 2009, 10:26:08 pm » posted from:Singapore,,Singapore

The above web page include two animation: refraction/reflection and thin lens refraction.
However, for the refraction/reflection part. I would suggest you to check out Intensity of reflected s-wave/p-wave.
When light enter into another media, reflection will always occurs.
The animation only show either reflection or refraction. It might introduce mis-concept about the light.

My thoughts:
Intensity of reflected s-wave/p-wave is indeed a superb approximation of the real life physics.

My Stand:
I agree with you that it is not appropriate to teach in binary reflection/refraction and may introduce mis-concept about the light.

My position:
NTNUJAVA Virtual Physics Laboratory Java Simulations in Physics: Enjoy the fun! is my favorite website for engaging in inquiry learning. That's why i am remixing and contributing back here. I learn a lot too.

My unfinished work:
I am in the process of refining this Ejs open source converging & diverging Lens object image high school java applet.

Cheers!
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lookang
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 « Embed this message Reply #6 on: July 19, 2009, 09:26:14 am » posted from:Singapore,,Singapore

found some popular lens java applet

1. http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=48
Likes: the white screen to illustrate possible focus image and blur images?
Likes: most popular java applet hosted all around the world

Likes: the white screen to illustrate possible focus image and blur images?
Likes: the option for no rays, principal rays, marginal, all rays to allow for sense making?
Likes: the move me! bouncing hints
Likes: movable principal axis lens to reposition lens

3. http://surendranath.tripod.com/Applets/Optics/ReflRefrCurv/CurvSurfApplet.html

4. http://webphysics.davidson.edu/physlet_resources/dav_optics/examples/eye_demo.html
Likes: fantastic for explaining eye lens

http://www.physics.uoguelph.ca/applets/Intro_physics/kisalev/java/clens/index.html

http://webphysics.davidson.edu/course_Material/Py230L/optics/lenses.htm
Like: the beam function
Like: Mirror
Like: Aperture
 lens.PNG (11.56 KB, 635x347 - viewed 998 times.)  lens01.PNG (27.84 KB, 646x536 - viewed 1070 times.)  len02.PNG (43.83 KB, 1024x768 - viewed 1129 times.)  len03.PNG (11.33 KB, 609x290 - viewed 954 times.)  image.png (29.4 KB, 835x391 - viewed 1125 times.) *** There are 2 more attached files. You need to login to acces it! « Last Edit: January 01, 2010, 04:54:54 pm by lookang » Logged
lookang
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 « Embed this message Reply #7 on: July 23, 2009, 01:46:26 pm » posted from:Singapore,,Singapore

i am done with improving this applet
Enjoy!

applet download available for registered users at the top of the post.
 « Last Edit: November 19, 2009, 04:36:20 pm by lookang » Logged
leeyiren
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 « Embed this message Reply #8 on: December 31, 2009, 08:38:35 pm »

to see the real image we need a screen. yet i notice most simulation dun include a screen. I request that someone create an simulation that is something like the one in this thread but add a screen that is adjustable so we can see how does adjusting the screen affect the image. thx
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lookang
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 « Embed this message Reply #9 on: January 01, 2010, 12:52:07 pm »

to see the real image we need a screen. yet i notice most simulation dun include a screen. I request that someone create an simulation that is something like the one in this thread but add a screen that is adjustable so we can see how does adjusting the screen affect the image. thx

I agree with your suggestion. Let me do some research on ways to show the sharpness of the image on the screen.

Good point.
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 « Embed this message Reply #10 on: February 10, 2010, 08:39:56 pm »

hi leeyiren,
i think the request you made is beyond me currently.
sorry can't help with that.
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 « Embed this message Reply #11 on: July 17, 2012, 10:26:58 am » posted from:SINGAPORE,SINGAPORE,SINGAPORE

changes.

Would it be possible to make the following changes?
1) Full screen capability like Fu-kwun with more space for image/object: Too little room to show image/object (always out of screen; and unable to show object/image at "infinity")
(I saw your auto function but would much prefer a fixed screen for ease of comparison)

made a checkbox to hide the top "use"
added input field and slider that are wider in range for exploring u = - infinity

2) Default uncheck blue line (with option to check it): In practice, we only draw 2 lines to determine the image. 3rd line is merely for checking answer.

i check http://www.physicsclassroom.com/class/refrn/u14l5ea.cfm
the better way to learn principal ray is 3, not 2.
i have added a checkbox for 2 ray but the default is 3

3) Option to add in "eyeball with retina" in background?

there is a screen, but i have no added sharp or blur effects as i do not know or seen any EJS that does that.

4) Disable â€“ve f (since eye cannot be â€“ve f and its not in syllabus)

i check http://www.physicsclassroom.com/class/refrn/u14l5ea.cfm
the better way to learn f is to have both sides of the lens.

1) To show that human eye lens is of variable focal length. We need to stretch/compress our eye to see far/near object
2) People with short sighted have a upper limit to their focal length
3) People with far sighted have a lower limit to their focal length
4) Old people can have both upper/lower limit to their focal length and hence need bifocal lens

need another applet like this one
http://webphysics.davidson.edu/physlet_resources/dav_optics/Examples/eye_demo.html

enjoy!
http://weelookang.blogspot.sg/2010/06/ejs-open-source-converging-diverging.html
 « Last Edit: July 17, 2012, 12:53:43 pm by lookang » Logged
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 « Embed this message Reply #12 on: August 03, 2012, 09:59:37 pm »

thanks to a feedback

Great Applet!  I was playing around with it and found that with a divergent lens, the image formed will be real. Is that right? I thought it will be a virtual image?

the bug has been fixed
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 « Embed this message Reply #13 on: August 04, 2012, 10:15:06 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE

thanks to lim yi xian

I told my classes Loo Kang edited the lens applet and what the lens applet was capable of doing, and the girls went "WAHHHH......"... Haha.. Thanks Loo Kang!
A little touchup to the applet if you got time LK:
for divergent lens light ray, the arrow should be dotted and pointing in opposite direction? See attached. Thanks again!

dotted lines is difficult (not available) in EJS, will not implement
opposite direction done thanks to http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=48
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 « Embed this message Reply #14 on: August 10, 2012, 09:43:50 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE

fix more bugs for converging virtual light rays arrows directions
 Screen shot 2012-08-07 at PM 12.53.03.png (12.91 KB, 345x270 - viewed 1023 times.)  virtuallightarrowcorrected.png (18.87 KB, 601x579 - viewed 894 times.) Logged
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 « Embed this message Reply #15 on: September 17, 2012, 02:12:29 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE

more teacher feedback
made a tinyurl for the students to access this applet more quickly
http://tinyurl.com/rgslens

I realized the virtual rays are still not "dotted" (or fainted) correctly.
The rays exiting the object should be solid ray (your red ray exiting object is fainted).
The rays entering the object from the image should be dotted and doesn't need an arrow head.

cheers!

need to understand what the teacher means
The rays exiting the object should be solid ray (your red ray exiting object is fainted).
The rays entering the object from the image should be dotted and doesn't need an arrow head.
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 « Embed this message Reply #16 on: September 19, 2012, 03:44:55 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE

dotted lines when the image is virtual and remove the arrows

managed to do corrected i hope for the green principal ray.
need to take a break for a while.

fixed the red lines in second attachment ejs_ThinLenModel01.zip
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engrg1
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 « Embed this message Reply #17 on: September 19, 2012, 08:51:03 pm » posted from:-,-,SINGAPORE

Looking at the old simulation remind me of the times when I am using Prof Huang's lens applet to teach my students about drawing ray diagram :-) That is like 4 years ago.
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 « Embed this message Reply #18 on: September 20, 2012, 03:48:34 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE

Looking at the old simulation remind me of the times when I am using Prof Huang's lens applet to teach my students about drawing ray diagram :-) That is like 4 years ago.
the older applet is here
www.phy.ntnu.edu.tw/ntnujava/index.php?topic=48

this a new version made in EJS

completed the dotted lines requested by teachers

"Also regarding the object at focal length, I think there should be no
image so is it ok to display v = infinity?
Although I know in theory, 1/f = 1/u + 1/v but is it still valid when
there is no image?"

but i check there is no image
 no_image_2012-09-20_1701.png (32.32 KB, 608x577 - viewed 1044 times.) *** There are 1 more attached files. You need to login to acces it! « Last Edit: September 20, 2012, 03:54:59 pm by lookang » Logged
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 « Embed this message Reply #19 on: October 01, 2012, 02:38:56 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE

more feedback!

1) Wow! Thanks bro you are truly amazing! )
The blue ray is not quite correct. I've attached a picture for your reference.

seems to have fix it now

2) u, h and F are in steps of 10. Could you change them to steps of 5.

done

3) Just found 2 new bug.
a) When F = 0, there is no lens.
Maybe for the slider, can skip F=0. If they want to key in, let them be.

change the value turn to 5 instead of 0 when 0 is selected

b) When F = 40, u = -10, the green ray is too short (doesn't cut F)

done! made it always reach the xminimum and xmaximum

enjoy!
 bug21sept2012.PNG (18.77 KB, 608x577 - viewed 1076 times.) *** There are 1 more attached files. You need to login to acces it! « Last Edit: October 01, 2012, 04:36:34 pm by lookang » Logged
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An interaction between two opposites produces a unique outcome. ..."Jules Henri Poincare(1854-1912, One of France's greatest mathematicians)"