No reason to unlike video ,, Very nice dear doctor Carry on for further inventions Regards

@BijuRaju

3 жыл бұрын

Thank you so much for the encouragement :-)

Keep the good work , Sir ! Congratulations !

@BijuRaju

3 жыл бұрын

Thank you so much, Dr. Breno, for your kind appreciation

I’m going to try it 🤣 thanks a lot!

@BijuRaju

Жыл бұрын

Did it work?

Awesome innovation sir.

@BijuRaju

3 жыл бұрын

Thank you, Sir, for the kind appreciation. I hope this was useful. Thank you

Very very useful. Thank you very much

Great Job!

Hi Doctor. Planning to do it this week. Kindly let me know if it works with multiple camera android phones and whether position of the flashlight on the phone matters?

@BijuRaju

Жыл бұрын

Yes, the position of the flashlight is important. If the flashlight is >1 cm away from the camera, then it is difficult to make the light coaxial.

Doctor, I have a 10D lens. What would be the length of the tube. I want to photograph very small flowers and insects with my phone

Nice!

@BijuRaju

2 жыл бұрын

Thank you

Sir , does brand of lens matters ?? I bought 1400 , 20 D lens from amazon , sir , i didn’t get good image with it

@BijuRaju

4 ай бұрын

I use Volk or Ocular. There are excellent quality lenses, but costly. Other brands may not give good images

Hii sir.....i am research scholar of IIT Bhubaneswar. Could you please explain why the tube length is 24 cm and how it is decided?

@BijuRaju

7 күн бұрын

Good question. I have no scientific data on this, but in my opinion, the distance between the flash and the camera of the phone determines the length of the tube. The farther the camera and the flash are, the longer the tube should be for the illumination and observation paths to be coaxial. If you can determine a formula for that, it will be helpful. Thank you

@smrutiranjansenapati8238

7 күн бұрын

Thank you sir.....I will try to find out it

Sir...how the length of tube is decided??

Lovely video i wanted to know what is that egg shaped thing in which you are testing fundus camera..

@BijuRaju

3 жыл бұрын

Thank you very much, Soumya. It is a model eye for practicing indirect ophthalmoscopy. laser procedures etc

@soumyashrivastava4423

3 жыл бұрын

@@BijuRaju nice for testing planning to buy one now for my experiments else family will throw me out on experimenting with them🤣

Hi, is a 20D lens the sama as a 5cm focal length biconvex lens.

@dr.biju where can i buy that eye model that you use in the video Please provide me with a link

@BijuRaju

2 жыл бұрын

I was looking for the details as well after I saw your comment. I think it was from www.akritieyecare.co.in/index.php?route=common/home But I couldn't find the model eye that I used on their online list. You can contact them directly and find out if they still have it

beautiful

@BijuRaju

3 жыл бұрын

Thank you so much Dr. Sushruth! Thank you for the encouragement

Can I use a 28D lens , for newborn examination ?

@BijuRaju

3 жыл бұрын

Yes, you can. but the 28 D lens being a smaller dia lens, you need to put the lens into the tube and you may need to add a round of tape on it to fix inside the inner part of the tube.

@JackBlack-ou5cu

3 жыл бұрын

@@BijuRaju Thanks for the reply Sir. I just made it ! I worked very fine with 20D , but I had too much glare with my 28D. Do you think the tube lenght should be different ?

@BijuRaju

3 жыл бұрын

@@JackBlack-ou5cu Can you send a picture to drbijuraju@gmail.com, that was taken with the 28D?

Sir, From where can I procure this camera, please guide.

Great job sir , where can we get the retina replica to test our device

@BijuRaju

2 жыл бұрын

I got it from this company - www.akritieyecare.co.in/index.php?route=common/home But that was few years ago. I am not sure they still make it. You may contact them directly.

@samarthamj4619

2 жыл бұрын

@@BijuRaju Thank you very much sir.

I want to make it with my 22 D lens, what should be the tube length

@BijuRaju

3 жыл бұрын

The length should remain the same, that's my guess, as the change in focal length (5 - 4.54 = 0.46 cm) is not much. Or maybe, you can reduce the length by 0.5 cm. If you are using the Panretinal 2.2 from Volk, then the dia of the lens is larger than 20D and therefore you will probably make the lens end of the tube thicker. I would love to know how your project turned out, thank you

@oladapoawodein7558

2 жыл бұрын

Well done, highly stimulating and educative.

Sir, I am getting 2 lighted spots in my field during examination. How to eliminate that?

@BijuRaju

2 жыл бұрын

Those are the reflections from the lens surface and those light spots are seen with the smartphone fundus documentation technique. Cross polarization with polarizers can help eliminate the reflections but will reduce the amount of light and the picture will be noisy. Cross polarization is done by placing a polarizer in front of the flash and another polarizer in an axis perpendicular to the first, in front of the camera.

The lens used is convex lens of 20 D?

@BijuRaju

3 жыл бұрын

Yes, Volk 20D Aspheric lens

@ashwintayade1100

3 жыл бұрын

The inner surface of the pipe is covered by sandpaper?? To prevent reflection?

@BijuRaju

3 жыл бұрын

@@ashwintayade1100 Yes, you are absolutely right. It is to prevent a phenomenon called dazzle - the reflections from the inner surface of the tube. It falls right on the center of the lens as 2 semicircular reflexes. The Sandpaper acts like a baffle to reduce the reflections. The grains of sand prevent the reflection of the photons onto the lens.

how about android phones?

@BijuRaju

2 жыл бұрын

Yes, you can

Is dialation required?

@BijuRaju

3 жыл бұрын

Yes, it can be used only in dilated pupils

@soumyashrivastava4423

3 жыл бұрын

Thanks

@soumyashrivastava4423

3 жыл бұрын

Are there any plans for making non mydriatic budget camera like this?

@BiancaAguglia

3 жыл бұрын

​@@soumyashrivastava4423 You might be able to make it work if you use an infrared LED and a white light LED. I read about it in a paper from professors at the University of Illinois at Chicago. The paper explains how to build a nonmydriatic fundus camera. They use a Raspberry Pi and a custom made dual LED, but they do mention an MIT project that only used a smartphone (no need for Raspberry Pi). The trickier part is getting the dual light LED. You'd have to make that too, using regular LEDs (one white light, one IR). They are very cheap. Here are links to the Raspberry Pi article that talks about the camera (1) and to the paper that goes into details about it (2): 1. www.raspberrypi.org/blog/an-affordable-ocular-fundus-camera/ and to the paper that goes into details about it 2. www.hindawi.com/journals/joph/2017/4526243/ Reference 12 in that paper is about the MIT project using only a smartphone. I'm actually trying to build such a camera myself, but it's slow going because I have very little science knowledge so I need to do a lot of reading and learning to understand basic things. 🙃 Anyway, I hope you can make it work. 😊

@soumyashrivastava4423

3 жыл бұрын

@@BiancaAguglia thanks. I also read the same in some paperr but trying to getthese LED's in India is difficult.