There are several companies that market Japanese OLW (Optical Light Works)scopes under their brand name.
Vortex, Bushnell Elite series, Sightron and Weaver V-series and Grand Slam series are some that come to mind. The best Hawke scopes in the Frontier series may be OLW as well, as they are claimed to be made in Japan.
If a company claims their scopes are made in Japan, it's a very good chance that OLW made them.
Scopes are a commodity market. Hardly any scope company grinds their own lenses these days. They set the specification and then most likely the lenses are ground in Japan or China, mostly China, using German glass or whatever is specified. The lens grinding machines are likely German, no matter what company in what country grinds the lenses.
In scopes, you get what you pay for. If you want everything made in Germany or Austria, be prepared to spend in the $2000-$3000+ range.
An exception would be Russian scopes, which are idiosyncratic and rarely found in the west. They are actually Russian made. Russians build about the best optics for the money found anywhere. They own the affordable night vision market.
I own a Russian telescope, and it blows away my "American" telescope that is partly made in China. The American scope uses American glass, but it is shipped to China and assembled into their mechanical optical tube assembly. The Chinese focuser failed almost immediately, which was replaced by an American aftermarket brand. The Russian scope has no such problems, and the finder scope mount is soi robust I use it as a carrying handle.
The Russian glass is far, far superior to my American glass. An American scope maker that buys some of his glass from LOMO, the maker of my telescope, said it was fully equal to Carl Zeiss standards. Carl Zeiss left the amateur telscope market, as LOMO did as well, as they could not charge enough to build to their quality standards against Chinese competition. LOMO is a very big maker of microscopes and medical optics, as is Carl Zeiss. LOMO made about 90% of Russia's best military optics, and much of their scientific and industrial optics, as well as the world's largest single mirror cell reflector telescope.
I suspect Russian rifles scopes are very good, but they have a definite military look to them, from what I have seen. I doubt that companies such as LOMO would be interested in competing against cheap Chinese hunting scopes when they can sell excellent scopes to military customers. In advanced night vision, they are second in sales volume to the USA, and may even surpass the USA soon. An optical dealer I know said the main difference between American optics and Russian optics was the price tag. The performance was so close as to not be an issue. Russians lack distribution and service centers in this country.
When a British television program tested the German 4X WWII Carl Zeiss sniper scope against the Russian 3.5X PU sniper scope, the Russian sniper scope was judged the best scope for military sniper duty.
There is probably nothing built (branded?) by Vortex that equals the very best Russian, German, Austrian or American scopes. By that I mean built in those countries, not just branded by a company that operates in that country.
Russia uprooted entire German optical factories (Zeiss Jena being one of them) and their workers and moved them to Russia after WWII. Do you think there is any way their optics are not world class? And they probably wouldn't bother to compare their best to a Vortex, which is a branding name and not a real manufacturer. I doubt that Schmidt & Bender or Swarovski are breaking a sweat as well. LOMO probably doesn't want to mess with mass market rifle scopes. A good scope is a lot more that optical quality out of the box, and you have to put it on a rifle and beat it to death for 10 years to see if it's the real deal.
