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Omid's Invention - Binoculars with Convergent or Divergent Field of View (1 Viewer)

Omid

Well-known member
United States
I received my patent grant on "Binocular telescope with controlled parallax" on August 29, 2017. It is US Patent Number 9,746,660 and you can read it here.

This is my 8th granted patent in the field of sports optics and the only one (so far) specifically dealing with binocular vision. My other patents are mainly on riflescopes.

In this patent, I have contemplated binoculars that have parallel tubes but diverging or converging fields of view. Human eyes have fields of view that only partially overlap. However, binoculars have field of views which nearly 100% overlap at long distance (because the barrels are parallel). Therefore, the "real" field of view of binoculars is the same as the real field of view of one barrel. In my patent, I have considered diverging the field of view of binoculars by a slight amount so that they still overlap at a nominal distance, but the two barrels will show more horizontal field than a single barrel.

It is also useful to make binoculars with converging field of view. These will be useful for observing very close objects, such as insects or flowers.

Feel free to review the patent and share your thoughts.

Thank you,
-Omid
 
I received my patent grant on "Binocular telescope with controlled parallax" on August 29, 2017. It is US Patent Number 9,746,660 and you can read it here.

This is my 8th granted patent in the field of sports optics and the only one (so far) specifically dealing with binocular vision. My other patents are mainly on riflescopes.

In this patent, I have contemplated binoculars that have parallel tubes but diverging or converging fields of view. Human eyes have fields of view that only partially overlap. However, binoculars have field of views which nearly 100% overlap at long distance (because the barrels are parallel). Therefore, the "real" field of view of binoculars is the same as the real field of view of one barrel. In my patent, I have considered diverging the field of view of binoculars by a slight amount so that they still overlap at a nominal distance, but the two barrels will show more horizontal field than a single barrel.

It is also useful to make binoculars with converging field of view. These will be useful for observing very close objects, such as insects or flowers.

Feel free to review the patent and share your thoughts.

Thank you,
-Omid

Yo, Omid, I don't need to see a patent to believe you are using "parallax" incorrectly. You have probably been listening to hunters who usually don't know the difference. You know, those guys who often say LEO-pold instead of LOO-pold.

Being able to dial in a single field for close focusing on insects and such is, in my opinion, a great thing; I find diverging fields annoying! But, collimation and parallax are different.

A binocular is collimated when the targets overlap without the need to resort to the user’s spatial accommodation within Panum’s fusional area to view a single field or image.

Parallax is alleviated when the focal plane of the objective coincides with the focal plane of the eyepiece. In instruments with errors in parallax, a motion of the head will move those planes relative to each other. This becomes VERY apparent and annoying in riflescopes.

Just a thought. :cat:

Bill

PS If I have misread something, I am available for beating. I'm used to it; I raised 3 teens.
 
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Hi Omid,

Feel free to review the patent and share your thoughts.

Sounds great, especially the capability for relaxed viewing of very close objects!

However, I'm curious about how your invention improves the three-dimensional viewing experience at long distances.

There seem to be no physiological limits like there are at short range, and without actually increasing lateral objective distance, stereoscopic perception would not seem to change. At least, that's what I would think from my limited stereo photography experience ... I'm probably missing something here?

Regards,

Henning
 
Yo, Omid, I don't need to see a patent to believe you are using "parallax" incorrectly.

Hi Bill,

It is not incorrect to use the term parallax to refer to the the spatial difference between left image and right image in binoculars. Parallax, by definition, is a displacement in the apparent position of an object viewed along two different lines of sight. In binocular images, parallax exists naturally because the object is viewed by two eyes. In a riflescope, a "parallax error" may occur when the target image and the reticle are not in the same focus plane AND if you position your eye away from the optical axis. In both cases, the phenomenon in question is caused by viewing an object from two eye positions and is correctly called "parallax".


Being able to dial in a single field for close focusing on insects and such is, in my opinion, a great thing; I find diverging fields annoying!

Yes, it is as you said. A normally collimated binocular -parallel barrels-is not suitable for viewing close objects. The convergence angle of objects viewed is amplified by the magnification of the binocular and will cause too much parallax between the left image and the right image. The brain can not fuse the two images into one 3-D scene.

See the attached image which is from a 1981 patent by Zeiss. It suggestes binoculars with converging barrels. This will solve the problem of viewing close objects but causes other ergonomic issues (e.g. adjusting the distance between barrels to fit the user's eyes).
 

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Hi Omid,

Sounds great, especially the capability for relaxed viewing of very close objects!

However, I'm curious about how your invention improves the three-dimensional viewing experience at long distances.

There seem to be no physiological limits like there are at short range, and without actually increasing lateral objective distance, stereoscopic perception would not seem to change. At least, that's what I would think from my limited stereo photography experience ... I'm probably missing something here?

Regards,

Henning

Thank you for you kind words. Yes, for short distance objects, we can reduce parallax and provide a more relaxed 3-D viewing.

At long range, I am with you: I am sure that we can increase the "stereo field of view" of binoculars by making their field of view slightly divergent (say by 1 degree). But can we also simulate the view of a binocular with "long inter-barrel distance"?? From one analysis it seems possible: Consider viewing a single object at a far distance. The line of sight from the left barrel and right barrel of the binocular to this object form a certain angle. One way to increase this angle is to separate the binocular barrels further. Another way is to slightly angle the barrels of the binocular (in my case, I do this optically, not mechanically).

Now, would the effect be the same (increasing barrel distance vs bending their line of sight)? I am not sure.. Let's think about it more and try to figure it out. Looking forward to hearing your thoughts.


-Omid
 
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Hi Bill,

It is not incorrect to use the term parallax to refer to the the spatial difference between left image and right image in binoculars. Parallax, by definition, is a displacement in the apparent position of an object viewed along two different lines of sight. In binocular images, parallax exists naturally because the object is viewed by two eyes. In a riflescope, a "parallax error" may occur when the target image and the reticle are not in the same focus plane AND if you position your eye away from the optical axis. In both cases, the phenomenon in question is caused by viewing an object from two eye positions and is correctly called "parallax".

Yes, it is as you said. A normally collimated binocular -parallel barrels-is not suitable for viewing close objects. The convergence angle of objects viewed is amplified by the magnification of the binocular and will cause too much parallax between the left image and the right image. The brain can not fuse the two images into one 3-D scene.

See the attached image which is from a 1981 patent by Zeiss. It suggestes binoculars with converging barrels. This will solve the problem of viewing close objects but causes other ergonomic issues (e.g. adjusting the distance between barrels to fit the user's eyes).

Hi Omid:

I want to THANK YOU ... and BEAT YOU at the same time! You have created a conundrum the ramifications of which I must think on—a lot.

Your definition was no different from mine when talking about ONE TELESCOPE, and I’m certain you will admit my definition conjures up more graphics and explanations than yours. However, your version allows for errors in alignment to be compounded. Now, in order to manufacture a quality instrument, we have to worry about errors along the Z axis of BOTH telescopes (if a reticle or reticles are in place) as well as errors in the X and Y (largely, but not exclusively) related to IPD.

You college pukes can be such pains. Still, I think I want to THANK YOU more than beat you!

Seriously, I would contact the archives department at Zeiss and find out why they didn’t put the patent into production. That might be a good place for you to start relative to getting a feel for the practicality of the concept. Remember, it’s opinion, not physics that makes the cash register ring. And as Aristotle said: “No bucks—no Buck Rogers.”

Did they back away:

1) Because the product would be too costly for the consumer
2) Because too few consumers felt they needed/wanted the feature
3) Because there were too many places for errors to creep in due to anomalies in production (See Vignette #41 in my book)
4) Because tilting the lines of sight—even a little—would change the Rx of aberrations in BOTH telescopes.

For a long time, I had a contact there. But he has been retired for years. BF’s Gary Hawkins ([email protected]) might be able to help. He used to work for the company. :cat:

Cheers,

Bill

PS Are you on Gene Cross’ list? That’s were the design heavy hitters hang out. BUT, unlike BF and CN, they are not chatters.
 
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Hi Omid,

Now, would the effect be the same (increasing barrel distance vs bending their line of sight)? I am not sure.. Let's think about it more and try to figure it out. Looking forward to hearing your thoughts.

My experience from old-fashioned stereo photography (shooting pairs of positives, and using a pair of slide viewers to view them) is that due to the inaccuracies in camera and viewer collimation (I guess that's the term :), and especially in mounting the slide in the frame, you usually end up with slightly bent line of sights.

That merely creates some amount of inconvenience when viewing the pictures. For some people, it's an instant headache - I can cope with it quite well, but it's still tiring to compensate for that.

Changing the lateral objective distance results in a different effect: The apparent scale of the stereo image changes. That is a bit of a problem in stereography because you basically have to adjust later objective distance when you adjust focal length to retain a realistic image.

Of course, you can also play with it ... a friend had a pair of slides showing a model railroad engine in 1/87 scale. The lateral objective distance used for taking this set of pictures was just 1 mm though. Viewing this picture, the brain scales up the model steam engine to life-size proportions, based on the natural lateral eye distance of roughly 87 mm.

The opposite effect is using two cameras mounted at normal eye distance, but using tele lenses ... everything will appear smaller than real life.

When it comes to binoculars, I would think that the only way to preserve a realistic stereoscopic impression would be something like the WW1 vintage Zeiss SF 14Z:

http://www.fernglasmuseum.at/museum...hweiz/zeiss_scherenfernrohr_sf14_schweiz.html

Not to say that there is no way to improve the 3D viewing quality without going to such extermes. I'd imagine that your invention would allow larger lateral objective distance than usual while still allowing a great view at very short range!

Regards,

Henning
 
Thanks for sharing. Let me start with asking if you have built functioning models of the binoculars?
Unfortunately I can't view the patent images.
My initial thoughts are those of doubt.
I need to make this disclaimer: I may have misunderstood the concept and am at the moment not in a position to dig into this based solely on your verbal description.

There are converging binoculars like the Papilio, which is also based on the reverse-porro build style. The objectives converge when setting focus closer and it works very well.

My objections concern the idea of using diverging objectives to increase 3D perception. The eyeballs then need to converge in order to fixate an object without diplopia. This could possibly be facilitated by the use of prisms in the eyepieces. The field stops would not almost coincide to a circle like in a normal binocular, but rather look like in comic strips with two image circles only partially overlapping.
The eyeball convergence means that the medial parts of the two FOVs of the binocular tubes are used, not the center, which usually is the sharpest part.
When roaming around with the eyes in the FOV, optical aberrations of the right and the left tube will differ. Last but not least, the increased FOV will not be common for both eyes since the medial fieldstops will not nearly coincide with the opposite side's lateral field stop.
There would possibly also be some blackout problems.

There are actually already devices that achieve what you're hoping to, namely traditional porros.
Their increased spacing between the barrels also increases the 3D perception. When used at closer distance than infinity, the parallax is present, the FOVs of the right and the left barrel overlap less and adjusting the IPD may be necessary to avoid excessive convergence.

//L
 
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Hi Omid,



Changing the lateral objective distance results in a different effect: The apparent scale of the stereo image changes. That is a bit of a problem in stereography because you basically have to adjust later objective distance when you adjust focal length to retain a realistic image.

Of course, you can also play with it ... a friend had a pair of slides showing a model railroad engine in 1/87 scale. The lateral objective distance used for taking this set of pictures was just 1 mm though. Viewing this picture, the brain scales up the model steam engine to life-size proportions, based on the natural lateral eye distance of roughly 87 mm.

The opposite effect is using two cameras mounted at normal eye distance, but using tele lenses ... everything will appear smaller than real life.

Great description of the effect of lateral objective distances and the perception of scale. Thanks.

Bill
 
Dear Bill, Henning, and Looksharp65 from Sweden,

Thank you very much for your valuable critique. I will respond to your comments point-by-point shortly. But in the meantime, I would like to give you access to the full PDF text of the patent. This should help understand the concept better:

http://www.omidjahromi.com/Optics/My_Patents/Finch/Omid_Jahromi_US_Patent_9746660.pdf

Thanks again,
-Omid

Your concept was a much better representation than the Zeiss drawing. WEDGES; light and precluding the need for much lost motion or a changing of the line of sight via an impractical separating of oculars. I like it. Now, see if “Mikey” likes it.

Bill
 
Seriously, I would contact the archives department at Zeiss and find out why they didn’t put the patent into production. ...

That's a good question. It could be any of the reasons you listed in your post.

There is at least one limitation in Zeiss design that doesn't exist in my design: In their design when you tilt the objective axis, the eyepieces also tilt. In my design, the real convergence angle on the objective side (Alpha) and the apparent convergence angle on the eyepiece side (Beta) can be manipulated independently. Also, as you yourself noted, I don't change the mechanical collimation state of the binocular barrels.

Not to say that there is no way to improve the 3D viewing quality without going to such extermes. I'd imagine that your invention would allow larger lateral objective distance than usual while still allowing a great view at very short range!

Henning

Thank you for articulating the effects of changing the baseline in stereo photography. A while back, one of the members here on BidForum introduced me to the book by Ferwerda on stereo photography. This is a very nice book and has a chapter on "converging camera axis" during stereo imaging (Chapter 9). Chapter 10 deals with changing the baseline as you mentioned. It is mentioned in this book that stereo images can be made using camera with converging axes if certain considerations are taken into account. So, that is reassuring.

In addition, stereo-photography is not exactly the same as stereo-observation using a pair of binoculars. There are some subtle difference in the principles of these two fields that I am still discovering.. ;)



I need to make this disclaimer: I may have misunderstood the concept and am at the moment not in a position to dig into this based solely on your verbal description. ... There are converging binoculars like the Papilio, which is also based on the reverse-porro build style. The objectives converge when setting focus closer and it works very well. ...My objections concern the idea of using diverging objectives to increase 3D perception. The eyeballs then need to converge in order to fixate an object without diplopia. This could possibly be facilitated by the use of prisms in the eyepieces.

Very interesting insights. Some of them I was familiar with and some were new to me. I posted the full PDF version of the patent so you can see the images and the description of the invention. In the patent I have considered manipulating the real convergence angle (Alpha) on the objective side and the apparent convergence angle (Beta) on the eyepiece side. Both Alpha and Beta can be increased or decreased to create various 3D effects. I look forward to hearing your feedback once you review the patent again. Thank you in advance for sharing your thoughts.

You are right about separating the field of view of the left barrel and right barrel of the binoculars: it creates an effect similar to when they show binoculars in the movies. But it is OK! I actually sometimes increase the IPD of my binoculars to create a similar effect. This way, the binoculars seem to have a wider field of view than when the two circles defining the field stops completely overlap.

-Omid
 
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Still not sure that I can understand what this actually adds. For many people, convergence is the only non-parallel eyeball motion. I happen to come with the added feature of structural divergence, basic exophoria, so I can induce diplopia whenever I wish to and sometimes when I don't.

I prescribed a fairly weak base-in (3 prism diopters in total) prism on each eye for myself in order to decrease the needed convergence.
This means that I maintain a small misalignment (squint) of my eyes's optical axises but the prisms bend the light inwards to coincide with my optical axises.

I made this little experiment with a roof binocular of mine with a 4 mm exit pupil. My IPD is 67.5 mm.
I watched an object 3 meters away and pushed the barrels together until I almost lost track of it because of the "miscollimation". The binocular's IPD was then 62 mm. After that I pulled the barrels apart so the binocular's IPD was 75 mm, all without losing track of the object.

Then I repeated the experiment at about 30 meters distance and the "usable" (well...) IPD was still 62 to 75 mm.
Since the optical axises of the barrels were parallel, in collimation, all that happened was that I looked with the same convergence at 3 m regardless of the binocular's IPD, and with parallel eyeball axises at 30 m, again regardless of the IPD setting.

No increased depth perception was detected, but the misalignment of the FOV's of the two barrels caused a decreasing viewing comfort. I guess it takes a significantly wider objective spacing difference than 7.5 mm to detect an increased 3D perception.
Edit: The constant 3D perception with the roof binoculars is real. Exactly nothing will change with changing the IPD. Only the wider spacing of porros provide the increased parallax needed to enhance the 3D perception.

If you use wedge prisms, their alignment must mirror the opposite side like in your drawings.
Any single-side rotation will induce a base up/base down effect that mercilessly will cause vertical diplopia.
Hence, a function that allows variable prism power/effect for different distances must have a synchronized bi-rotational coupling where one prism rotates clockwise and the other anti-clockwise.
This way, diplopia will be avoided, but the binocular's position (angle vs. the horizontal plane) must also be adjusted because the bilateral base up or base down prisms will change the vertical position of the image.
Rotational prisms like those in phoroptors allow keeping the image single, but are a bit ungainly.

When using binoculars at infinite distance, both FOV's should show exactly the same image. If they don't, they are miscollimated or the internal field stops are dislocated.
Used at finite distance, traditional porros will have a slightly better depth perception thanks to the wider objective spacing. An object at finite distance will appear closer to the medial edge of the FOV's with these, which requires some convergence and sometimes also an IPD adjustment. The IPD adjustment towards narrower does not change the convergence, only move the image away from the medial edge towards the center so that the FOV's align better.

Roof binoculars, with their narrower barrel spacing, will not displace the image of an object towards the medial part of the FOV as much as porros do. The smaller parallax will here mean that you look at the object with less convergence and some 3D clues will be lost. They do however benefit from a perceived greater magnification emanating from the brain when convergence decreases. The real image size is not altered.

Not very many people can diverge with their eyes and when we do, we experience diplopia, not added field of vision or enhanced 3D perception. We may tend to avoid situations and devices demanding excessive convergence.

Heterophoric people can not diverge with their eyes when looking far away, only have a relative divergence at close viewing, which basically means they can sometimes converge less if given a base-in prism.

Esophoric people tend to have full or excessive convergence and cannot benefit from convergence-relieving prisms.

You could go to an optical shop and ask to borrow "wedge prisms" from the trial lens kit.
Experiment with putting them in front of the objective (you actually only need to do this unilaterally) and/or behind the eyepiece. Look at various distances to judge whether or not it works at all and whether or not it adds any of the increased image qualities you hope to achieve.

Addendum: I have the strongest objections to the depiction of the beam path in your Fig. 2(a).
All beams the human vision can detect are either parallel or diverging. If they're parallel, their origin is far away, ideally infinitely far.
Beams coming from a closer object diverge, which means that we can perceive them when we converge.
The beam path shows parallel beams entering the objectives and converging beams exiting the eyepieces.
This requires divergence of the eyeballs, something I can perform but the majority cannot.

Even more so with Fig. 3(b) which depicts converging beams, which is against all logics and laws of optics since they would emanate from an object beyond infinity. Only parallel or diverging beams go from natural objects. (except for the eye lenses of many animals)

Just a few thoughts, maybe not very well put together but hopefully food for thought.



Regards,

Lars
 
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Not up to Lars's standard in the above post 13.
Just an observation below.

I bought about 30 6x18 Waterproof yellow roof prism binoculars with independent eye focus. £7.50 each.

10 were good with good star images and good alignment for me at least.

10 were not very good but usable with some strain.

10 were useless, but if cut in half would make good monoculars.

Amongst the 10 not so good were some with good alignment for me but vastly non overlapping field.
Although they worked they were uncomfortable to use because, for a start, the binoculars have curved fields.
This curvature is beneficial because I set the good ones for distance viewing and can see closer objects by using the lower field parts. So no focus is needed.
But with the much wider horizontal field examples the field curvature and other aberrations affect the view.

The best binoculars were given to friends and relatives.
They still use them after 10 years.
And they remained waterproof in a basin overnight.
They are very lightweight and small.

The point is that the ones with say 25% non overlap have much wider fields horizontally than vertically.
I think that in aligning these binoculars the operators just made them work even though the barrels are in considerable mechanical misalignment.

Because I have little accommodation I don't like this wide system at all, but some younger folk might find them useful.
 
If my post was difficult to understand, it may be because I accidentally wrote heterophoric when I meant ortophoric. Mea culpa!

I should also clarify that I with "Even more so with Fig. 3(b) which depicts converging beams" mean that the beams converge before entering the objectives. Hope this clears things up!

//L
 
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I don't know if I am heterophoric or not. :)

Ill ask my lady.

P.S.
I looked it up.
I think I am slightly heterophoric.
 
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:t:
If my post was difficult to understand, it may be because I accidentally wrote heterophoric when I meant ortophoric. Mea culpa!

I should also clarify that I with "Even more so with Fig. 3(b) which depicts converging beams" mean that the beams converge before entering the objectives. Hope this clears things up!

//L

Lars, you just mixed things up a little - don't be so hard on yourself :-O
 
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The point is that the ones with say 25% non overlap have much wider fields horizontally than vertically.

Yes. That's how "perfect" binoculars should be. Individual human eyes don't have a circular field of view and further their fields of view don't overlap 100%. An ideal binocular should have a field of view with an aspect ratio matching that of human vision.

In my concept, I achieve this effect by slightly diverging the "real" field of view of each barrel. This doesn't mean the eyes need to diverge to view the images shown through the eyepiece. This is an important point. I will explain it further in a separate post.

-Omid

PS. An ideal binocular should not be requiring horizontal gaze with eyes looking parallel. The most comfortable vision is when the eyes are looking about 15 degrees downward and converging a bit as in looking at an object just a few meters ahead (not at infinity). There! I just gave you material for a new invention ;)
 

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If you use wedge prisms, their alignment must mirror the opposite side like in your drawings. Any single-side rotation will induce a base up/base down effect that mercilessly will cause vertical diplopia.

Hi Lars,

Thank you very much for your exhaustive and detailed comments. I keep learning from your posts. Now, regarding the point that wedge prisms must be aligned so that they only induce horizontal change in the angle of view, I agree completely. The prisms must be connected to the binoculars (and potentially to each other via a rod) so that their orientation always remain base-in or base-out (whatever was designed originally) when the IPD distance of the binoculars are adjusted by the user. In most binoculars, the barrels rotate about the optical axis when IPD is adjusted. The prisms should be excluded from this rotation.


Not very many people can diverge with their eyes and when we do, we experience diplopia, not added field of vision or enhanced 3D perception. We may tend to avoid situations and devices demanding excessive convergence.

Nowhere in my design do I require the user to diverge his eyes. When I suggest that the real field of view of the binocular objectives are made slightly divergent, this still requires the user to converge his eyes to see an object located at a far -yet finite- distance. Consider a point object positioned in front of the binoculars and perfectly centered with respect to the two barrels. With normal binoculars (parallel fields of view), this point object will appear on the right side of the image in the left barrel and to the left side of the image in the right barrel. Now, if the field of view of the objectives are made slightly divergent using thin wedge prisms as I suggest, the same point object still appears on the right side of the center of image in the left barrel and on the left side of the image on the right barrel. What changes is that you need even more convergence to view it since the image moves farther from the centers and closer to the edges of the image shown in the eyepiece.


Addendum: I have the strongest objections to the depiction of the beam path in your Fig. 2(a). All beams the human vision can detect are either parallel or diverging. If they're parallel, their origin is far away, ideally infinitely far.

The figures don't show the beams that are observable or usable to human eyes. The diagrams show, in very simplistic ways, how the prisms affect the direction of central light rays (the direction of view).

A hardware patent such as mine is focused on describing the physical structure of the device being patented. A patent should describe extremely clearly what the parts of an invention are and how those parts are connected to each other. If the apparatus so described produces one "useful" result, it is sufficient. This result may or may not be novel; it is the "structure" that must be novel. Many other effects and results may be obtained from the binoculars I have described. ;)

Thank you again and looking forward to hearing any other comments you may have.

-Omid
 
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