The closest distance to the object within the in-focus range (observation distance) is called the closest distance.
The closest distance has characteristics depending on the type of endoscope.
1. Endoscope equipped with advanced camera
Since there is a camera at the tip, the optical closest distance is longer.
In the case of our endoscope, the closest distance is 10 mm.
The recommended viewing distance is 10-60mm.
Although it is made by another company, some low-priced models seem to have a closest distance of about 40mm.
2. Borescope
Borescopes and fiberscopes have relatively short closest distances.
This is not a guaranteed value as there are individual variations, but when connecting a camera with our borescope, the closest distance is approximately 5 mm.
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Lens focus tonality can be adjusted, but there are limits. The limit is around 5mm. |
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When we checked with our current product, the closest distance was 4.5mm. |
◆How to shorten the closest distance
By inserting a close-up ring (5mm), the closest distance can be reduced to about 3mm.
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When using our current product with a close-up ring (5mm), the closest distance was 2.5mm. |
The “borescope camera” used this time is available at our company.
Additionally, our Borescope Camera Adapter Lens is equipped with a 5mm close-up ring as standard.
For details, please see the product page below.