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Another lens patent has shown up today. This time an EF-S 17-55 f/3.5-5.6 IS STM. Perhaps it'll be a new kit lens this year and will replace the current 18-55 IS STM. However, this may also be a hold over from last years kit lens update.
Description and self-interpretation of the patent literature
- Patent Publication No. 2014-21258
- Publication date 2014.2.3
- Filing date 2012.7.18
- Example 2
- Zoom ratio 2.92
- Focal length f = 18.50-32.89-54.00mm
- Fno. 3.49-4.39-5.80
- Half angle ω = 36.44-22.55-14.20 °
- Image height Y = 13.66mm
- 119.77-110.06-120.23mm overall length of the lens
- BF 37.98-52.51-74.3mm
- Example 3
- Zoom ratio 3.09
- Focal length f = 17.50-32.05-54.00mm
- Fno. 3.47-4.38-5.80
- Half angle ω = 37.97-23.08-14.20 °
- Image height Y = 13.66mm
- 119.55-108.81-118.68mm overall length of the lens
- BF 36.59-51.53-73.93mm
- Canon patents
- 4-group zoom of positive and negative positive negative
- Inner folder – Kas (Group 3)
- The fourth lens unit can also be used for anti-vibration
Source: [EG]
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