The word “Asahi” was a common theme among Japanese companies as Asahi loosely translates to “morning sunrise” which was a symbol of the Japanese people, and was the inspiration for the red circle on the Japanese flag.  There were more companies that used the name “Asahi” in their name.
Asahi Optical Co. Ltd, was originally called ‘Asahi Kogaku Goshi Kaisha'. It was established in November 1919 in a suburb of Tokyo, called Toshima. The company didn’t produce camera’s at that time. Asahi started with the production of eyeglasses.

In 1923 they used their skills in polishing glass to produce projection lenses, binoculars, and other scopes.  They sold their products under the name “AOCO” which was an abbreviation for Asahi Optical Company.

In the 1930s Asahi started to make camera and photographic lenses. In 1932, Asahi commenced to make lenses for the Molta Camera Company. A company that is now known under the name Minolta. In the page under Minolta you can find more about this famous camera company. The lenses were ment for a 6,5 x 9 cm folding plate cameras.

In 1933 they began to supply Konishiroku, a compagny which was in the second hallf of the 20th century known under the name, Konica. Asahi produced a range lenses for their Pearl and Pearlette series of cameras.These lenses were not sold under their own name, but were produced under the names Zion and Optor. It is unclear whether Asahi designed the lenses, or just manufactured them to the specifications of their customers, but whatever the case, their previous abilities with eyeglasses and projection lenses gave them ample capacity and speed to make the lenses quickly, allowing both Konica and Minolta to establish themselves in Japan’s early camera industry.

In 1938 the company was reorganized by the Japanese government to produce optical products for the Japanese military up through the end of the war. There is little known about Asahi’s exact role during the war. It is not clear if they produced lenses to be used in military products manufactured by other companies, or if they supplied complete optical assemblies such as binoculars or other kinds of scopes for the military. 

By the end of the war, nearly all of Asahi’s factories in Japan were destroyed, and the company was forced to close. But not long after the war the president of Asahi, Matsumoto, convinced the occupying Americans to help re-establish the company in a new factory. The company was now named Asahi Optical Company, Ltd.

Asahi’s first product after the war was a telescope specially made for viewing the eclipse of the sun that year, 1948, in Japan. Because of the shortage in supplies the telescope was made out of cardboard, but the telescope was popular because of Asahi’s high quality lenses that were used and was quite popular. Also in 1948 they realised binoculars which were of high quality and helped to establish Asahi as a serious competitor in the Japanese optical market.
This was for Matsumoto, president of Asahi, the moment to expand the production into cameras. The market was overflown with German rangefinders and their Japanese copies. Before the war Matsumoto himself had owned a Reflex-Korelle 6x6 SLR. One of the first, and arguably the first, SLR ever to go in production. In 1949 he decided to go for this concept, the Single Lens Reflex.
Asahi had no experience in building cameras and the first designes were not successful. Matsumoto contracted some camera builders he knew from the past and with the help of this two men, Ryohei Suzuki and Nobuyuki Yoshida, Asahi succeeded in building the first prototype of the Asahiflex.

Then in 1950 a new war broke out, the Korean War. Japanese cameras became more and more popular. Especially the Leica and Contax coupled rangefinder copies that were produced by Nikon and Canon.
In 1949 the Asahi designers had developed a prototype of a 35mm SLR camera, the Asahiflex.This camera wasn't based on the Leica or Contax rangefinders. Although 35 mm SLR’s existed in Germany, like the Contax D and the Kine Exakta, Asahi did’t copy these cameras either. These cameras were not exported to Japan and so not easily available.

The Asahiflex was designed entirely from scratch.although it had much in common with another German camera, the ‘Praktiflex’. As the Praktiflex the Asahiflex was equipped with a waist-level viewfinder and a mirror which rose when the shutter button was pressed. The mirror fell back to its viewing position when the shutter button was released. The ground glass screen provided a bright image the correct way up, but reversed from left to right. It takes a lot practise to get used to this design. It was acceptable for horizontal shots, but framing and focusing a vertical picture was almost impossible. The answer to this problem was a small viewfinder on top of the camera.

The new camera was introduced to the Japanese home market in May 1952.
The lenses that came with the camera were called ‘Takumar’. A strange name for lenses but there is a little story behind that name. Takuma Kajiwara was a Japanese photographer living in the USA at the time. But on top of that he was not only a relative to both the founder and the president of Asahi but also an associate of George Eastman, the founder of ‘Kodak’.
The Asahiflex was the first Japanese 35mm single lens reflex camera. But not for long because other manufacturers also saw the potential of the design of by a moving mirror viewing through the lens and began to develop their own SLR’s.
A big problem of the concept was the fact that the viewfinder was blocked by the mirror and therefore was blacked. Another big problem was that the focusing screen, because of the set aperture, gave a very dark image and was therefore hard to focus.
But for almost all problems there is a solution. By 1953 the Takumar lenses were fitted with a pre-set aperture ring which allowed focusing to be done at open aperture and therefore a clear focusing image. After focusing a second ring made it possible to close the lens to the selected aperture without removing the camera from the eye.
he problem of lens blackout had been overcome
In 1954 with the introduction of the Asahiflex IIB the instant return mirror was introduced. This overcame the problem of lens blackout. The mirror returned to viewing position as soon as the shutter had fired.
Asahi can’t righty claim that they were the first to incorporate an instant return mirror into a camera. In 1947 quick-return mirror had been used in a Hungarian camera. Although this camera wasn’t reliable and it certainly wasn’t produced in big numbers.

The next major step in the development of the Single Lens Reflex cameras was made by Asahi in 1957. They introduced a built-in pentaprism and they named the camera Pentax.
The rights on the name had been acquired from East German VEB Zeiss-Ikon/ Pentacon. The engraved name on the camera front and the briljant design were so successful that later the whole company was labeled Pentax like this 35 mm camera model. Because of the pentaprism this camera realised a very bright focusing screen, and an image that was the correct way up and unreversed. This Asahi Pentax AP was the first Japanese SLR to incorporate a pentaprism system.
Another big difference between the Asahiflex and the Asahi AP was the lens mount. The 37 mm screw thread lens mount was replaced with a 42 mm that was already in use with the German Pentacon and Practica cameras. This meant that the 37 mm Takumar lenses couldn’t be used on the new cameras.
The Asahi Pentax AP was the first SLR with a film rewind crank and fast lever advance instead of a rewind and film advance knob, which made taking a picture and changing film much easier and faster. The camera was equipped like the Asahiflex-II, with an instant return mirror.
The East German Contax D was the first camera with a pentaprism but the Pentax had a much brighter finder due to its first fresnell-lens matt screen.
This was not only the smallest, lightest and comfortably operated camera at the market. It was the primeval design for all SLR cameras to come. It became the world standard. And even in 2022 not only DSLR cameras but mirrorless camera like Sony A serie and the Fuji X serie have the design concept of this camera from 1957.
The Asahi AP with the pentaprism system started a new photographic era. Until then the range finder cameras had dominated the 35 mm professional market, but now their days were numbered.
In the first year 19600 Asahi Pentax AP were built. In he USA the cameras were sold as Tower 26 and Tower 29.

Further developments as for instance the introduction of built-in exposure meters took place. Asahi had developed an exposure meter which sat atop of the pentaprism and was coupled to the shutter speed dial of Pentax models S1a and SV.
The earlier models S1, S2 and S3 could easily be updated by the user to use this exposure meter.
The Pentax S1 was an "econmy model" missing the 1/1000s. A modern cds-meter could be placed on the prism of the camera.
The next major step was taken in 1960. Asahi had developed a prototype camera which took exposure measurements through the taking lens. The camera was called the Spot-Matic.
With a standard 50mm lens the exposure meter took a spot reading from the focusing screen of the in focus subject.
The Spot-Matic however was not introduced to the market until 1964 as a result not Asahi was the first manufacturer that introduced TTL metering but Topcon. The Topcon RE Super was available for buyers in spring 1963. By 1964 not only the name of the Asahi Pentax camera was slightly changed in Spotmatic, but the exposure meter was changed from a spotmeter to a average reading exposure meter.
The Pentax cameras from 1957 to the Spotmatic look very similar and are technically based on the same construction, sharing many if not most parts. To distinguish them from the Spotmatic-family (slightly larger body) the whole line is called Pentax S-series.

The year 1975 saw another major change took place. For several years Asahi had been using the 42mm screw mount for its SLR cameras. But most of its competitors used by now bayonet lens mounts. It was a enormous step for Asahi to change las mount, because they had thousands and thousands of users who had been building up outfits based on the screw mount for years. But the screw mount had reached the end of its useful life. The last Pentax cameras with the screw mount were the Pentax Spotmatic F and ESII models.

Three new cameras based on the Spotmatic and ES models were introduced in 1975. All three were equipped with the new designated K-Bayonet. And not without succes because until today 2022 the Pentax lenses and cameras are fitted with the K-mount form 1975. Older Pentax users could buy a adaptor ring with which the old screw mount lenses and accessoires could be used on the new cameras.
However, this had a big price because all lens automation was lost when the adaptor was used.

The new models were called KM, KX and K2. More information about this cameras on the Pentax K pages.

Now not long after the introduction of the K-serie cameras Pentax made a nieuw move. In 1976 they came up with the Pentax M-Series. This was Pentax answer to the trend towards smaller and lighter cameras. The trend had been started by Olympus with their OM1 and later the OM2. The first two models of Pentax in this concept were the MX and the ME. The ME was a fully automated simpler version of the K2 and the MX a shrunken KX.
The M serie further developed in the next years cumulating in the absoluut topmodel the professional Pentax LX in 1980. Although the LX belonged to the M series Pentax gave it an other name. LX stood for the Roman numbers LX for sixty to celebrate Asahi sixtieth anniversary in 1979.
In 1981 Asahi Pentax introduced world’s first TTL autofocus SLR camera, the ME-F.
Today people complain that camera compagnies introduce new models to fast after each other.

All this innovations showed of in the sale figures for Asahi. In 1966 Asahi had produced and sold one million SLR cameras since 1952.  But in the next three years they managed to sale another million in 1969. In 1981 they reached the figure of ten million SLR cameras since 1952.

Prices

Asahiflex without the slow shutter speeds cost in 1957 $ 79,50 in 1957 Tower 22 f 3.5 lens. for 2022 that means: 
Asahiflex met lage sluitertijden $ 99,50 in 1957 Tower 23 f 2.4 lens
Asahi AP met 2.4 lens $169,50

In Germany there was no Pentax sales office until 1968, and German photo.shops didn't sell Japanese cameras. In USA the price was avout 250USD (Mail-Order; incl. lens). This was a competitive price for a high-class camera that it was. A LEICA M3 was about 350 USD, Nikon SP 329 USD, Exakta VX Automatrik 398 USD (with ~f/2 lenses). In 1960 sellout prices for the "K" body  dropped to 100 USD (without lens). Like the "Asahi-Pentax" of 1957, the "K" model was produced one year only - 21.5000 units - a respectable number..