Soldered lenses
May 13, 2008
A dosing head heats small solder balls with a laser beam and accurately shoots the melted droplets onto the lenses to fix them perfectly in place. Credit: Fraunhofer IOF
Lenses in optical devices are kept in place by adhesives. This can cause problems when the microscopes and cameras are employed inside a vacuum, as the adhesives may release gases that contaminate the lenses. One alternative is to solder them instead.
When cameras and microscopes are placed in a vacuum, their functionality can be seriously impaired. This is because their lenses and prisms are normally fixed with adhesives, which release gases inside the vacuum. The gas molecules settle on the lenses and alter their optical properties. At high temperatures, too, or when using lasers in the UV range, the adhesives cause problems: They become soft or brittle, and the optical components can slip by several micrometers.
Researchers at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena have now developed an alternative in a joint project with engineers from Pac Tech GmbH in Nauen. “We solder the optical components instead of gluing them,” says IOF group manager Dr.-Ing. Erik Beckert. “This has a definite advantage: The solder material is resistant to extreme temperatures and radiation, and also conducts heat and electricity.”
To enable them to apply the solder to the lenses just as flexibly as an adhesive, the researchers adapted the ‘solder bumping’ technique normally used in electronics manufacture. Small balls of solder contained in a dosing head slip one by one into a capillary, where a laser beam heats them until they become liquid. The liquid solder droplets are then shot by a nitrogen pressure pulse to the spot where they are needed to fix the lens. Once in place, the solder cools in just a few milliseconds and solidifies.
“This process can be automated and is very flexible. We can apply the solder downwards or from various other angles and in places that are difficult to access,” says Beckert. Solder bumping is much faster than gluing. While it takes 10 to 30 seconds to apply an adhesive and let it harden, soldering takes less than one second. To ensure that the solder does not come off the glass lenses, they have to be metallized in advance, for instance in a sputtering process which can be carried out on a large scale.
A special feature of the solder bumping process is that it does not need a fluxing agent. “Normally, flux is used to ensure that the solder fully coats the metal. However, in a vacuum, the flux residues would outgas in a similar way to adhesives. The lens system would have to be thoroughly cleaned before being used. That’s not necessary with the flux-free version,” says Beckert.
At Optatec, which will take place in Frankfurt (Germany) on June 17 through 20, the researchers will present prototypes of optical components fixed in place by solder bumping. Beckert hopes that the system will be ready for use in production in a year or two’s time.
Source: Fraunhofer-Gesellschaft
-
Robot speeds up glass development
Nov 07, 2011 |
not rated yet |
1
-
IBM researchers unveil green optical network technology prototype
Feb 28, 2008 |
4.6 / 5 (81) |
1
-
Precision bonding makes tiny high performance actuators possible
Oct 03, 2005 |
not rated yet |
0
-
Molecular wires and corrosion control boost performance of conductive adhesives
Mar 14, 2005 |
not rated yet |
0
-
Closing the Loop: Georgia Tech Researchers Develop New Data-driven Closed-loop control for stencil printers
Jul 26, 2004 |
not rated yet |
0
-
Fast photon control brings quantum photonic technologies closer
1 hour ago |
5 / 5 (2) |
0
-
Engineers build first sub-10-nm carbon nanotube transistor
Feb 01, 2012 |
4.9 / 5 (33) |
30
-
Something old, something new: Evolution and the structural divergence of duplicate genes
Jan 31, 2012 |
4.6 / 5 (7) |
1
-
The hidden nanoworld of ice crystals: Revealing the dynamic behavior of quasi-liquid layers
Jan 30, 2012 |
5 / 5 (5) |
1
-
Stock market network reveals investor clustering
Jan 27, 2012 |
3.9 / 5 (23) |
8
-
How to tilt a object
14 hours ago
-
How to calculate total compressibility in liquid porous solid system
19 hours ago
-
Need help reading 3-D
Feb 11, 2012
-
A way to send and receive wireless data
Feb 11, 2012
-
Calling function with no input argument
Feb 10, 2012
-
Force free body diagram problem on gym equipment
Feb 10, 2012
- More from Physics Forums - General Engineering
More news stories
Independent group inspects Apple supplier
(AP) -- An independent group, the Fair Labor Association, has started auditing Apple Inc.'s Chinese supplier Foxconn after a request by Apple.
29 minutes ago |
not rated yet |
0
Teaching teens safety in the virtual world
A new cyber safety program on the dangers of social networking is being developed by Flinders University, in light of an alarming report which shows children as young as 12 are meeting internet strangers in ...
1 hour ago |
not rated yet |
0
Ethanol mandate not the best option
Many people are willing to pay a premium for ethanol, but not enough to justify the government mandate for the corn-based fuel, a Michigan State University economist argues.
Technology / Energy & Green Tech
1 hour ago |
5 / 5 (1) |
0
Microsoft India retail site down after 'cyber attack'
Microsoft said Monday it was investigating an attack by hackers on its Indian retail website, reportedly carried out by a Chinese group called the "Evil Shadow Team."
4 hours ago |
not rated yet |
0
Chinese city seizes Apple iPads in name dispute
(AP) -- Authorities have seized Apple iPads from retailers in a city in northern China due to a dispute with a domestic company that says it owns the iPad name, an official said Monday. The Chinese company said it is asking ...
4 hours ago |
not rated yet |
0
Fast photon control brings quantum photonic technologies closer
(PhysOrg.com) -- Using photons instead of electrons to transmit information could lead to faster and more secure ways to communicate, among other advantages. Now a team of physicists has taken another step toward realizing ...
Planck mission steps closer to the cosmic blueprint
(PhysOrg.com) -- ESA's Planck mission has revealed that our Galaxy contains previously undiscovered islands of cold gas and a mysterious haze of microwaves. These results give scientists new treasure to mine ...
New ability to regrow blood vessels holds promise for treatment of heart disease
(Medical Xpress) -- University of Texas at Austin researchers have demonstrated a new and more effective method for regrowing blood vessels in the heart and limbs a research advancement that could have ...
Myths and shame keep many from seeking bankruptcy protection
(PhysOrg.com) -- Two interesting facts that may counter modern ideas about bankruptcy: The overwhelming majority of U.S. filings belong to individuals rather than corporations or entities, and most of these ...
Big Society could threaten biodiversity conservation
A study of the Moray Firth Seal Management Plan (MFSMP), in north-east Scotland, identified four key conditions for long-term success, three of which pointed to the importance of direct government involvement.
Motivation to exercise affects behavior
(Medical Xpress) -- For many people, the motivation to exercise fluctuates from week to week, and these fluctuations predict whether they will be physically active, according to researchers at Penn State. In an effort to ...
May 13, 2008
Rank: 1 / 5 (1)