Have you ever wondered how camera lenses are manufactured? Why it takes days to make a new lens? Well, here’s an interesting look into how lenses for DSLR cameras are made. It takes a total of six weeks to make one optical lens. Camera lenses go through several inspections to make sure that the glass gets to the final stage without defects or any dust particles on it.

Here’s a video that demonstrates how camera lenses are made -

The Process:

There are four main manufacturing processes.

• Grinding and Polishing lens elements
• Coating lenses
• Producing the barrel
• Assembling the lens

The videos show a step-by-step procedure on how a Canon 500mm lens is made. These videos were taken in Canon’s lens manufacturing factory in Japan.

In the above video, you can see that the manufacturing of the lens  goes through a series of steps. Here are the lens manufacturing steps as shown in the above videos:

1. Material blending
2. Pre-fusing
3. Melted glass is allowed to cool naturally
4. Cutting the glass into pieces
5. Fusing
6. Mixing
7. Churning
8. Clarification
9. Homogenization
10. Shape the glass into sheets
11. Shaping and pressing process
12. Grinning processes
13. Heating the glass and form its shape by pressing (by hands or by automatic machines)
14. Annealing
15. Further polishing
16. Rough grinding that produces that curved surface of the lens
17. Fine grinding
18. Polishing and surface curvature adjustment
19. Optical inspection
20. Clean with ultrasonic washing machines
21. Alignment
22. Coating
23. The lens assembly process itself (done by hand for Canon L lenses)

Hat tip to Digital Photography Writer for sharing this.