Featured Small porcelain cup with secret.

Good day everyone. There is such an unusual item in my collection, I coudn't identify it, literally zero information. I can't find another cup like this.
For truth, I didn't know for many years that there was a picture there.. It's hard to see it because the glass is all scratched.
Height 3.2cm, diameter 5.2cm.
Would appreciate any suggestions

 

Different decoration design and portrait, but same concept:
https://chidorivintage.com/products...yomizu-ware-kohai-guinomi-ochoko-sakazuki-g46
https://www.ebay.com/itm/126245231472?chn=ps&_trkparms=ispr=1&amdata=enc:1YVDrrNecS-C6GOiwFI7l2Q55&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=126245231472&targetid=1585159290651&device=c&mktype=pla&googleloc=9016835&poi=&campaignid=19894961968&mkgroupid=148855406073&rlsatarget=pla-1585159290651&abcId=9307911&merchantid=6296724&gclid=CjwKCAiA5L2tBhBTEiwAdSxJXyRS1g0am5W_2uCuoYYhftMq2pNTY35vMHtyk69I9Dt7SRmoSVQ2mhoCZVsQAvD_BwE
I've seen these hidden picture sake cups referred to as "magic eye".

 

Thanks a lot!! Design might be Russian, woman with kokoshnik and jewelry. The firebird is also like a reference to Russian mythology. Just thought.

 

Is that writing in the red swoosh?

 

Unfortunately..

 

Is that called, or similar to, a Stanhope?

 

You have to put liquid in them to properly see the hidden image. I have a set.

 

SHE was HARD to 'pull out'!!!! But unable to make her any 'sharper'.....

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It's about microphotography, but this is something about the effect of refraction of light.. But close, I think
Because of background and blurriness of the picture, I assume that it is drawn.

This is impossible even to the human eye

 

@bluumz called it correctly, Sake cups. And @Aquitaine brought out the picture which is obviously a geisha with one of those elaborate headdresses. I don't think the black marks on the swoop is writing or a signature, just marks on the swoop-part of the decoration.

 

Agreed.