Author Topic: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.  (Read 2936 times)

Offline OtisBrown

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The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« on: June 02, 2013, 07:42:16 PM »
Dear Friends,

Here are the concepts for your interest.

Here is Ronald's theory of accommodation:

Schachar Mechanism of Accommodation


The Schachar mechanism can readily be demonstrated with an air-, water-, or gel-filled biconvex Mylar balloon. Counter-intuitively, when equatorial force is applied to a balloon with an aspect ratio (minor axis/ major axis) of less than or equal to 0.6, its central surfaces steepen and its peripheral surfaces flatten. This shape is called a "steep profile" and is a universal phenomenon, which can be demonstrated in floating oil films, vesicals, and water droplets floating in space. The formation of a steep profile may explain the evolution of a discy elliptical galaxy into a lenticular galaxy. Note the image below.

Details:


http://emedicine.medscape.com/article/1219573-overview#aw2aab6b4

Was Helmholtz was correct?


Offline OtisBrown

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Re: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« Reply #1 on: June 02, 2013, 07:44:33 PM »
Hi Todd and other successful plus people,

Here is a short review of what researchers have found - to avoid entry into myopia, and in some cases, get out of it.  I personally "limit" what I am willing to suggest is possible, to highly motivated people who can still objectively read the 20/50 to 20/60 lines on their "home Snellen" chart.  This is a good read for "optometrist thinking".

http://myopiafree.i-see.org/PREV73.TXT

Dr. William Ludlum wrote a paper on "submariners" developing negative status for their natural eyes - based on the time they spend in the submarine.  That seemed perfectly logical for the natural eye to behave that way - so I wrote to him.  He sent me to Dr. Raphaelson who supported the concept that threshold prevention would be possible - if the plus were worn BEFORE you go below 20/60. 

(You can call this Raphaelson's theory of the natural eye's accommodating to long-term near.   What I was interested was in what he did for his own children - and was he successful with them.  I think we have "myopic minds" when we fail to take a broad perspective - but that is my "take" on these interesting issues. )

+++++

Hi John,

I believe that there knowledge was very limited - and that you truly can not "isolate" the eye's total change of power to "just" the internal lens of the eye.  There is evidence that the entire eye "accommodates", thus if the eye has a total power of 60 diopters, and you look at an object at 13 inches, the natural eye changes its total power from 60 to 63 diopters.  No one has been able to be more accurate than that statement.  I agree with that concept.  The rest is un-proven speculation about some details of how the natural eye changes its total power by sensing "micro-blur" at the fovea, and making the required refractive power changes.  This concept was also suggested by Dr. Bates - but he did not go into this type of extensive detail.


Offline OtisBrown

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Re: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« Reply #2 on: June 03, 2013, 03:19:28 AM »
Subject: Todd's success.

In the final analysis - it does not matter which concept that you use (and there are perhaps 10 good theories) - it only matters that you personally verify your own success - as Todd did.

Peace,

Offline OtisBrown

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Re: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« Reply #3 on: June 04, 2013, 05:53:58 AM »
Subject: Two theories of the totally natural eye.

1) The preferred "Box Camera" assumption - taught in physics classes.

2) The alternative "Dynamic Eye" concept - where the eye is accepted as dynamic - in the first place.

It is not that one theory is "right", but that one is more accurate in predictive capability - than the other.  (Note:  I draw a "line" around and OD or MD's office - and will not "argue" with them.  They have a minus lens that obviously "works", and no one wants anything else.)

This mistakes of ASSUMING that the natural eye is not a dynamic system. Part 1

Subject: Why prevention, at -1.0 diopters could become successful. The “ray-trace” theory – we were taught in high school and in college.

The concept presented here seems to be “perfect science”. It is an “analysis protocol”, a concept developed by Johan Kepler (yes, in 1610), and further expanded in 1865 by Helmholtz. It is very easy to JUMP to the conclusion that a natural eye with a measured refractive STATE of -1.0 diopters – is an eye that is ‘too long”. This is a tautology. Yes, AFTER your natural eye responds to “long-term near” it CHANGES its refractive state – to a measured negative value. In fact, in viewing this ray-trace presentation I began to ask, “… what would happen if you took an eye that was PERFECT, (refractive state of zero). With “diverging light-rays” would this natural eye “… make itself longer”. Or perhaps the concept of “too long”, was a presumption, based on VERY LIMITED DATA. Here is the presentation.

(Video to posted at the end of this presentation.)

If you begin asking the question of the dynamic eye, and its response to a minus lens – you get a different, and objective picture of an eye that is indeed “highly responsive to long-term near”. It then takes on a negative-state (avoid the assumption of, “too long”), and this negative STATE can be avoided its “early stage”, by getting the natural eye to avoid “diverging light-rays”, or “rays of light from long-term near”. Thus proof that they eye is responsive to

1) Diverging rays of light and

2) Long term near, are equivalent. You prove the NATURAL eye’s responsiveness to a -3 diopter lens (takes on negative state), and you prove (for the analytical intellectual) that long-term near creates negative status – for the same reason. But it takes the ability to visualize the concept.

Offline OtisBrown

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Re: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« Reply #4 on: June 04, 2013, 05:55:57 AM »
Subject: They dynamic eye concept (Eyes measured has having refractive STATES - never presumed errors.)

Part 2 – The experimental reality of the dynamic eye.

Subject: I like scientific simplification and clarification.

The previous “ray trace” picture of the eye – is presented as “perfect, PROVEN science”. If you begin to point out the “failed assumptions”, that a naturel eye with a negative state is not PROVEN to be “too long”, but rather can have a TEMPORARY negative status, that in a limited sense could be changed from a -1.0 diopter to +1/2 diopter, you are told you are a “ignorant in basic science” because you will not “buy into” the above ray-trace analysis. The “trace-analysis” is correct, only if you assume the eye is “too long”. But it is always a “neat package”, where a obvious, but wrong assumption is made. If you think in terms of a “dynamic eye”, and objective testing, “i.e., black-box, input, compared with output”, you get proof for this paradigm:

(Videos in next post.)

The issue in pure-science, is to finally respect the truth that all natural eyes are dynamic, and a mistaken assumption was made to create the ray-trace analysis.

Obviously, you will never get this type of analysis in an OD or MD’s office. Yet it is critical to understand the consequence of this New Science and the fact that “negative status” is indeed the product of the behavior of the totally natural eye. This is an engineering problem, not a medical problem.

Offline OtisBrown

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Re: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« Reply #5 on: June 04, 2013, 06:07:14 AM »
Subject:  I always like a video presentation of a concept.  Here are the two video's of these two theories of the totally natural and normal eye.

Theory 1>  Box camera - assumed to be correct for mathematical calculations.

http://www.youtube.com/watch?feature=player_embedded&v=VDehC_Txa1U

Note:  I was taught this in college - and would teach it myself when required to do so.  It is understandable, and the "product" a minus that works in an office - is equally understandable.  However, assumptions are made to make this "conceptual model" work.  I would warn the person that this is an idealization, and never reflects experimental reality.

Theory 2> Dynamic-eye Camera:

http://www.youtube.com/watch?v=PxLv7BIxnIU

Thanks to thoughtful ODs, the issue becomes one of prevention, at the threshold, by wearing a plus (while you still can read the 20/40 line). There is a scientific basis for wearing the plus (for all close work) but doing so is based on this "theory" of the natural eye.  There are people who require "animation" for understanding - and that includes me.  I in no sense "fault" the prescription of a minus lens in an office - but I my judgment, it is based on the idea that is mistaken.

If you are comparing concepts - this is one way to do it.

Enjoy,

Offline OtisBrown

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Re: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« Reply #6 on: June 05, 2013, 05:14:04 AM »
Subject:  Look at concept #2.  Then ask yourself who is going to tell you the truth?

( I will remove this is a few days - but it is good to understand this issue of optometrist-anger. )

Albert OD>  Hi, I'm an Optometrist. And you're right about one thing, and that is - I hate this video! But I hate it simply because you are misleading people to believe a mis-informed half truth, which makes it a lie.

Here is the video  for your interest:

http://www.youtube.com/watch?v=Tr0a1pEaavo

+++++

There is indeed scientific truth - but you define this to yourself.  For me "personally" - I look at my own Snellen and make certain I objectively pass the required DMV test.

Peace,

Offline OtisBrown

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Re: The Helmholtz, Bates, Donder Raphaelson Theory of the Eye.
« Reply #7 on: June 05, 2013, 05:20:14 AM »

Otis>  Given the OD's (implied) truth is that 1) Long-term near has NO effect on the eye's refractive STATE, and its derivative that 2) A minus lens is PROVEN to have no effect - and you have this tragic problem as defined by Dr. Alex.
 
Subject: Why you will never “hear” about threshold prevention in an OD’s office.
 
Reference: Why there is no choice but to “do prevention yourself”.

 
I have always been in favor of being told the “brutal truth” – that if I (at 20/40) do not wear the plus – my refractive STATE will continue down at a rate of –2/3 diopters per year.
 
http://www.frauenfeldclinic.com/glasses-creating-dependency-for-a-product/
 
That to me is like “putting on weight” – when I know how I can (must) control my own weight (by sitting up, and intentionally wearing a plus for ALL close work).
 
Tragically very few parents will listen to that type of “pure-science” advice – so I do “give up”.
 
The primate eye (and its idealization) is a bitter truth – that I now understand.
 
But dealing with a child at 20/50, and –1.0 diopters – is almost impossible.  (If child or parent “object” to it – then it is impossible.)
 
Very few people have the courage to tell "theory 2" brutal truth.

I can "accept it" - but I do not like it.