Jump to: navigation, search

Pentax is a Japanese camera maker, founded in 1919.


The company that would become Pentax was founded in 1919 as Asahi Kōgaku Kōgyō G.K. (旭光学工業㈾). It was originally an optical company, beginning by making glasses under the Aoco brand (presumably the acronym of Asahi Optical Company), and made its first Aoco projection lens in 1923.[1] It began to produce camera lenses in the early 1930s, under the impulsion of the CEO Kajiwara Kumao (梶原熊雄) and his closest collaborator Matsumoto Saburō (松本三郎).[2] These lenses were not marked as made by Asahi, and were produced lenses for various camera models made by other makers. From 1933, the company produced Optor and meniscus achromat lenses designed at Rokuoh-sha for Konishiroku models. From the mid-1930s to the end of World War II, the company was also the main supplier of Molta, then Chiyoda Kōgaku Seikō (predecessors of Minolta), whose cameras were equipped with Coronar and Promar lenses.[3]

The company changed status in 1938, becoming Asahi Kōgaku Kōgyō K.K. (旭光学工業㈱) or Asahi Optical Co. based in Tokyo.[4]

The first camera produced by Asahi was the Asahiflex, that was also the first Japanese 35mm SLR, made as a prototype in 1951 and released in 1952. One of the models of the Asahiflex series, the Asahiflex IIb, was the first 35mm SLR to have an instant-return mirror, thus solving the problem of mirror blackout which had plagued SLRs up to that time (early SLRs left the mirror in its "up" position until the camera was wound for the next shot, blacking out the viewfinder).

Pentax was originally the name of another 35mm SLR camera model, introduced in 1957 and successor of the Asahiflex. The name is derived from the shape of the prism used in SLR cameras (pentaprism), and the ending deliberately looks like the Zeiss Ikon Contax. In fact, the name Pentax was a property of Zeiss Ikon (West) until they sold it to Asahi Optical Co., maybe strategically because ZI's East-German concurrent had relabeled its Contax S SLRs to Pentacon.

Many Pentax cameras were sold stamped with the name "Honeywell". Actually Honeywell was only a distributor, and these cameras were exactly the same as the ones stamped with the Asahi name. But more and more Pentax became a big brand, especially for SLR. Thus after a while the company offered not just 35mm SLRs but also complete camera systems around its Pentax 67 SLR for rollfilm and its tiny and popular Pentax Auto 110 for type 110 film cassettes. And in 1975 Pentax tried to take the lead with a new lens bayonet with same flange/film distance as the M42 screw mount, thus making it easier for lens makers to offer lenses for both mounts. In fact it should be an open bayonet standard, and really, a handful of other renowned camera makers used the Pentax's K-mount too: Zenit, Topcon, Chinon, Cosina,Ricoh, Samsung. But most important: The mount was further developed and still in use for Pentax's digital SLRs and even for one of its CSCs.

The company kept the name Asahi Optical Co. until it became Pentax Corporation (ペンタックス㈱) in 2002. After successful prototyping since 2000 the company launched its first DSLR in 2003, with Pentax K mount. A merger with the Hoya Corporation was completed on October 1, 2007. The new name is Hoya Pentax HD Corporation (HOYAペンタックスHD㈱).[5] In summer 2011 Hoya announced that it will sell the imaging branch of Pentax to Ricoh[6] while it will keep the medical branch of Pentax for itself.

In July, 2011 Ricoh announced its intentions to purchase the Pentax photographic-equipment business from Hoya (who, however, will retain some Pentax-branded medical product lines, etc)[7]. In August of 2013, the name of the company has been changed to Ricoh Imaging. The Ricoh branding are to be used on compact cameras while Pentax branded products will be on DSLR, interchangeable lens compact cameras and binoculars.



Medium Format SLR

Interchangeable-lens compact

Point and Shoot Cameras





  • Pentax EI-100
  • Pentax EI-3000 - prototype
  • Pentax Optio 330
  • Pentax Optio 430




  • Pentax Optio MX
  • Pentax Optio 30
  • Pentax Optio S40
  • Pentax Optio S4i
  • Pentax Optio 43WR
  • Pentax Optio S30
  • Pentax Optio S50
  • Pentax Optio S5i
  • Pentax Optio X
  • Pentax Optio 750z
  • Pentax Optio SV
  • Pentax Optio MX4


  • Pentax Optio WP
  • Pentax Optio 50
  • Pentax Optio S5n
  • Pentax Optio S45
  • Pentax Optio S55
  • Pentax Optio S5z
  • Pentax Optio SVi
  • Pentax Optio 60
  • Pentax Optio S60
  • Pentax Optio S6
  • Pentax Optio WPi
  • Pentax Optio 50L


  • Pentax Optio A10
  • Pentax Optio E10
  • Pentax Optio T10
  • Pentax Optio M10
  • Pentax Optio W10
  • Pentax Optio S7
  • Pentax Optio A20
  • Pentax Optio W20
  • Pentax Optio M20
  • Pentax Optio T20
  • Pentax Optio E20


  • Pentax Optio E30
  • Pentax Optio T30
  • Pentax Optio M30
  • Pentax Optio A30
  • Pentax Optio W30
  • Pentax Optio M40
  • Pentax Optio E40
  • Pentax Optio Z10
  • Pentax Optio S10
  • Pentax Optio A40
  • Pentax Optio V10


  • Pentax Optio E50
  • Pentax Optio M50
  • Pentax Optio S12
  • Pentax Optio V20
  • Pentax Optio W60
  • Pentax Optio M60
  • Pentax Optio E60
  • Pentax Optio E65


  • Pentax Optio P70
  • Pentax Optio E70
  • Pentax Optio E70L
  • Pentax X70
  • Pentax Optio E75
  • Pentax Optio W80
  • Pentax Optio P80
  • Pentax Optio E80
  • Pentax Optio WS80
  • Pentax Optio M85
  • Pentax Optio E85



  • Pentax Optio RZ18
  • Pentax Optio S1
  • Pentax Optio WG-1
  • Pentax Optio WG-1 GPS
  • Pentax RS1500

35mm film

K-mount autofocus SLR

K-mount manual focus SLR

Pentax K series:

Pentax M series:

Pentax A series:

Pentax P series:


Screw-mount Pentax SLR

Asahiflex SLR


  • Pentax Espio IQZoom series (e.g. Espio, Espio 928, Espio 115, Mini, IQZoom 135M Date, Zoom60-X, Zoom95-WR)
  • Pentax PC series (e.g. PC-33, PC35 AF-M, PC-300 Date, PC-606W)
  • Pentax Mini Sport 35AF (35mm, f/3.8)
  • Pentax Pino series (e.g. Pino 35M)
  • Pentax Sport (DX)

645 Medium Format

Manual Focus


6×7 Medium Format


110 film

1979-1983 interchangeable lens SLR

APS film



Pentax have produced many different types of lens for the K-mount. They are summarized in the table below.

Type Focus Focal Lengths Produced Zooms/Primes Lens Coverage Auto Aperture? Aperture Ring?
K Lenses Manual 15mm-2000mm Primes 36x24mm (35mm film) No Yes
M Lenses Manual 20mm-2000mm Both 36x24mm (35mm film) No Yes
A Lenses Manual 15mm-1200mm Both 36x24mm (35mm film) Yes Yes
F Lenses Screw-drive Autofocus 17mm-600mm Both 36x24mm (35mm film) Yes Yes
FA J Lenses Screw-drive Autofocus 18mm-300mm Zooms 36x24mm (35mm film) Yes No
FA Lenses Screw-drive Autofocus 20mm-600mm Both 36x24mm (35mm film) Yes Yes
D-FA Lenses Screw-drive Autofocus 50mm, 100mm (macros) Primes 36x24mm (35mm film) Yes Depends on lens
DA Lenses Screw-drive / SDM Autofocus 10mm-560mm Both APS-C Yes No


Hand held

  • Pentax 1/21 Spotmeter
  • Pentax 3/21 Spotmeter
  • Pentax Spotmeter II
  • Pentax Spotmeter III
  • Pentax Spotmeter V
  • Pentax Digital Spotmeter
  • Pentax Digital Spot V

Asahi lenses on cameras from other makers

Not all examples of the cameras listed below have Asahi lenses.

Lenses not labeled as by Asahi

For Konishiroku:

For the predecessors of Minolta:

The Heliostar lenses were perhaps assembled by Asahi (see the discussion there).

Lenses labeled as by Asahi


  1. Yazawa, p.12 of Camera Collectors' News no.247.
  2. Yazawa, p.12 of Camera Collectors' News no.247.
  3. The Coronar and Promar lenses are attributed to Asahi in various sources, and this attribution is confirmed by the "Kokusan shashinki no genjōchōsa" ("Inquiry into Japanese cameras"), lens items Lb5, Lb39, Lc9 and N2.
  4. Its address in 1943 was Tōkyō-to Itabashi-ku Itabashi-chō (東京都板橋区板橋町). Source: "Kokusan shashinki no genjōchōsa" ("Inquiry into Japanese cameras").
  5. Japanese version of the news release (archived) found in the Hoya official website. The name "HOYA PENTAX HD Corporation" is written in capital letters.
  6. Summer 2011: Hoya confirms sale rumours.
  7. Hoya press release (archived) (PDF) on sale of Pentax assets to Ricoh
  8. Pentax Classic DSLR concept at Watch Impress


  • "Kokusan shashinki no genjōchōsa" (国産写真機ノ現状調査, Inquiry into Japanese cameras), listing Japanese camera production as of April 1943. Reproduced in Supuringu kamera de ikou: Zen 69 kishu no shōkai to tsukaikata (スプリングカメラでいこう: 全69機種の紹介と使い方, Let's try spring cameras: Presentation and use of 69 machines). Tokyo: Shashinkogyo Syuppan-sha, 2004. ISBN 4-87956-072-3. Pp.180–7.
  • Yazawa Seiichirō (矢沢征一郎). "Renzu no hanashi (157) Happī" (レンズの話[157]ハッピー, Lens story [157] The Happy). In Camera Collectors' News no.247 (January 1998). Nishinomiya: Camera Collectors News-sha. Pp.11–4. (On the beginning of the company.)


Official websites

User groups and community websites

Technical information

In French :

In Spanish :