Cosina’s patent application was published on March 18, 2021. There are some examples such as “APO-LANTHAR 50mm F2”, but some of them are interesting such as “135mm F2” and “135mm F1.2”.
- [Publication Number] Japanese Patent Application Laid-Open No. 2021-43376 (P2021-43376A)
- [Publication date] March 18, 2021
- [Application date] September 12, 2019
- [Title of Invention] Imaging Optical System
- [Applicant]
[Identification number] 391044915
[Name or name] Cosina Co., Ltd. - PROBLEM TO BE SOLVED: To obtain a bright interchangeable lens which reduces fluctuations of various aberrations in the entire shooting distance range from a distance to a near distance and stabilizes them, and which covers sufficient optical performance in a shooting lens in a wide-angle range to a medium telephoto range. ..
| Example 1 | Example 2 | |
| Focal length | 40.00 | 36.01 |
| F value | 1.97 | 1.23 |
| Half angle of view | 28.4 | 31.4 |
| Example 4 | Example 5 | |
| Focal length | 51.14 | 49.28 |
| F value | 1.26 | 1.93 |
| Half angle of view | 22.9 | 23.7 |
| Example 9 | Example 10 | |
| Focal length | 73.00 | 134.00 |
| F value | 1.73 | 2.03 |
| Half angle of view | 16.5 | 9.17 |
| Example 12 | Example 11 | |
| Focal length | 25.80 | 134.00 |
| F value | 1.86 | 1.20 |
| Half angle of view | 39.9 | 9.17 |
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