Innovation probably wouldn't help. The over 100 year old Nikon Porro-Prism design of their 7x15 Mikron is for all practical purposes as good as the modern roof prism Leica Ultravid 8x20 compact IMO. A Porro-Prism is a more efficient design than a roof especially when it comes to light transmission and when you add high quality glass and updated coatings like Nikon did with the Anniversary 7x15 Mikron in most cases they are going to outperform or be neck and neck with the latest roof. Case in point is the Swarovski Habicht Porro's. They have updated EL glass and coatings with a simple porro design. Outside of edge sharpness they give up very little to my Swarovski SV's and they have better 3D and are brighter with 96% light transmission.
Edmund
Of course I agree with you that the porro design is solid mature tech! And engineers love tried and true solutions!
I have asked in various places, and am getting conflicting reports on the usability of the Mikrons from people who own them. As you point out, the competition are the miniature roofs, and it's not obvious who wins. Here is a typical anonymised contribution:
"I have five or six of the "since 1917" marked 6x15 or 7x15 Nikon Mikron binoculars. These were sold as fairly high end binoculars ($300-$400 +) from around 1997 I think. I believe that B & W photo had one of the models still available new until a year or two back, but don't seem to today so I assume they were selling NOS after production ended. They had all the modern coatings and are bright for binoculars of the small size. I dug a new pair out of 7x15s out and a pair of 6x15's and the rubber eyepieces are usable with glasses on do limit the view quite a bit. New ones are still readily available on US Ebay but shipping from Japan around around $270-$290 or so, and they seem to be marked since 1917, so presumably are NOS anniversary editions..
The older 1950's/1960's 1970's Nippon Kogaku & Nikon with silver metal eyepieces don't work with glasses, but those with plastic eyepieces will work with the black eyepieces removed. Limited in coatings.
But none of the miniature binoculars have a lot of light gathering capability anyway.
Innovation might be eg. 6x20 or 7x20, and really good eyecups/eyeglass protectors. Or even re-doing the 5x15 with rubber eyecups and updated prism glass. I don't see why Leica should claim that the Ultravid HD Plus is a class better than the HD because of the Schott glass prims, and then suddenly when it comes to porros the spectral transmittivity of the prisms doesn't matter.
Innovation might take place in the porros precisely because it is a good design that works, and so it could be conjugated in various form factors exactly like the roofs. Leica and Zeiss now do 8x20, 8x25, in addition to 8x30, and afaik these smaller ones sell well, see all the raves here about the Zeiss Victory 8x25. .
I have just carried my Ultravid HD 7x42 on a seaside vacation for 3 days, and they have been wonderful, I used them on a bunch of gulls in particular, but most of the time I would prefer to walk around with a bino in my pocket rather than a huge thing slung over my shoulder. After a couple of miles of beach, the weight starts to speak almost as loud as the image. One interesting factor with the 8x42 btw is that at dusk/night one loses color much faster than acuity. By day looking through the bino is like a direct look, at dusk the bino gets dark while direct view is still fairly light. This disturbs me as a painter but might not disturb a normal user.
I can afford a pair of new Mikrons or used small roofs, but I do want to get something that will be useful in practice.
Edmund