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Kazumi Okuda''s Other Invention

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Superidealist

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Kazumi Okuda, whose name some here will recognize as inventor of the Okuda diamond grading microscope (a precursor to the Firescope), filed this patent way back in 1976. I find it interesting that he proposed the inscription be placed on the culet.
 

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Superidealist

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Your link doesn't work.

The patent I linked to is the only one of his I could find in the US Patent Office database. That's not to say it's not there, though, or in some other patent database.

I know Fleimstaler (from DiamondTalk) emailed you scans of the documentation for Okuda's microscope. If you still have these, I'd be interested to see them.
 

Garry H (Cut Nut)

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http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=/netahtml/search-bool.html&r=1&f=G&l=50&co1=AND&d=ptxt&s1='Okuda;+Kazumi'.INZZ.&OS=IN/"Okuda;+Kazumi"&RS=IN/"Okuda;+Kazumi"
United States Patent 4,219,199
Okuda * August 26, 1980

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Diamond with molybdenum bonded thereto


Abstract
A diamond with molybdenum bonded or linked thereto comprises a diamond structure subjected to a pre-sputtering process by causing gaseous ions to impinge on a selected portion of its surface, and molybdenum bonded to said diamond structure, which has been subjected to said pre-sputtering process, by a sputtering process, forming a molybdenum film of 10 to 50 A in thickness bonded or linked with the diamond and which cannot be dissolved with hydrogen peroxide. The diamond may be in the shape of a record stylus which has been soldered to a stylus holder by coating the molybdenum film with copper, or other metal suitable for cementing by solder.
 

Superidealist

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Maybe you two could each post what you have to a new thread on just this topic. There is very little information out on this instrument. It would be interesting to see how it compares to both the Russian grading loupes that preceded it and the Firescope that followed it.
 

denverappraiser

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And a table view.

I've no clue what the table down view is supposed to look like and I'm sure there is a trick that I'm not smart enough to work out. The table itself provides a terrible reflection and I haven't played with it enough to find a solution. The manual would be helplful.

Neil Beaty, GG ISA
Independent Appraisals in Denver

tableview1.jpg
 

Superidealist

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Below is the Zeiss Proportion Loupe that operates, I imagine, similarly to Okuda's loupe. This idea dates back to at least the 1960's (from what I've heard) and seems more similar to the Firescope and Ideal-Scope than does the Okuda microscope.

In Okuda's microscope, it appears from the pages Garry has posted that there is no illumination from the pavilion side, though it's not entirely clear. This seems to be a key feature of the Firescope and Ideal-Scope and this feature is shared by proportion loupes where the diamond's pavilion is to be held facing a light source. Beneath is a graphic showing how to grade using a proportion loupe.

zeiss_pre_loupe.jpg
 

denverappraiser

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This is definitely my device.

The green light seems to be a light shining on a 2-way mirror at an angle in the middle of the viewing tube, as illustrated in the book. This results in a green light shining directly down the same path that the user is viewing. The instructions seem to say that you should look for the glare off of the table in order to establish that the viewing angle is directly perpendicular to the table. There are mechanical adjustments on the holding table and a scale inside the viewing lens, rather like those found on a rifle site, to allow the user to place the stone with the culet in exactly the center of the viewing area. The grading is apparently done with the green light turned off and the mirror rotated out of the way. There is another fluorescent light surrounding the tube that lights the stone quite nicely that is apparently used during the grading. It all seems to be designed to make the viewing environment as repeatable as possible over several different stones and over a long period of time. The grading itself seems to be based on the skills of the user and has nothing whatever to do with the green light. This looks to me like it’s for alignment purposes only.

There is no illumination from the pavillion side.

Does anyone else have one of these? Can anyone tell me anything about it?

Neil Beaty, GG ISA
Independent Appraisals in Denver
 

Superidealist

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On page five of the manual, it says that the green light is to be turned on during proportion grading.
 

Iiro

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Interesting Neil,

Can you make a new photo with a super ideal cut diamond?
 

Garry H (Cut Nut)

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Bump for Neil.

For SI / Riley, you asked "what is the Okuda principle" on a less appropriate thread. Thought I would answer you here as we would like to keep the Book threads on


I named the Okuda principal a long time ago because I thought Okuda was the first to develop the "colored light reflection or structure illumination concept" and hence devices like the Firescope, H&A's viewers, my early teaching devices with additional colored rings added to my firescope, then the Gilbertsonscope and finally the ideal-scope and the new AGS scope (ASSET I think is what they will call it). but it seems that the Russians got there first?

I would love to know who really was first to employ the "principle"

You have raised the issue that the Okuda MS only supplys light from above - with no "leakage light" from below. I still consider this to be in the same class. Interestingly AGS are not usuing back light - especially for fancy shaped stones.
 

Superidealist

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Performance-based assessment predates Okuda's microscope, but I have no idea who invented the Russian grading loupes that seem to have been the first implementation of what the labs are only now starting to adopt as a standard. Assuming these originated in Russia, maybe Serg would be better able to track down the person to whom the credit is really due.

The only thing I know about ASET is what was posted in your earlier thread on the Moscow diamond cut conference. Anything else you can tell us?
 

denverappraiser

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Garry,

Sorry to be slacking on this. It's a problem of being an Independent Appraiser. I'm planning to take the photos Iiro requested but I don't have a stone to photograph since I don't sell diamonds. The first group of pics was of one of my color masters but none of those could even laughably be described as super-ideal. I've been waiting for something appropriate to come through from a client who will give me permission to broadcast their photo. I'll see what I can drum up from the neighbors in the building.

Neil Beaty, GG ISA
Independent Appraisals in Denver
 

denverappraiser

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Ok, here's a pretty good stone.

0.74cts
5.76 x 5.81 x 3.57mm
Crown 35 degrees, 15.0%
Table 56.6
Pav 40.7 degrees, 42.7%
1.2% culet
M-Sl. Thick Girdle

I took a picture with the green light on but, as I mentioned, I think this is just for alignment purposes. I don't think it's intended to illuminate particular facets for use during the grading process. It's kind of a problem to take photos through the scope because the little scale screws up my focus but I'll play with it some more. as time allows.

Picture #2 is what I think is the correct view when following the instructions. The large piece surrounding the optic tube is a fluorescent ring light. this light is mounted on a bracket with an adjustment feature to allow moving the light closer and farther away from the stone with a scale marked in degrees to indicate where the light is placed. The range of the scale would suggest that it's about crown angles. Adjusting the light placement makes some substantial changes in the image but, again, I'm having trouble getting a decent picture.

Picture #3 is an I-S image of the same stone.

I suspect that this crown angle scale has to do with instructions that are not in the 5 pages we see. As I adjust it, I don't see anything interesting happen as I pass through the known crown angle but this may have to do with the way I'm holding the stone. There are two brackets for holding the stone. One is for mounted stones and one is for table down viewing. I've made an adapter to see the stone face up so I may be missing a piece.

Can I presume that Kazumi Okuda is not available to discuss the details?

Neil Beaty, GG ISA
Independent Appraisals in Denver
 
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