At the top of the device is a horizontal slit

 
    If you remove the beads and see these metal clips, call a glazier as these clips can be really tough to get rid of with out the appropriate tools.Back gasket program - Fit the glass and beads as described above and then push the rubber gasket back into the frame on the inside of the window. If the rubbers have shrunk you can gently stretch then out and re-fit them with a smaller blob of superglue in each and every corner to stop them from shrinking back once again.Security tape system - Fit the new tape to your window frame, taking care to maintain it flush with the frame edge. Remove the covering and Spray the tape with window cleaner. This will allow you to move and align the Double Glazed Unit. The window cleaner will evaporate in a couple of hours leaving you with a Double Glazed Unit that can only be removed by cutting it out from the inside. Fit the glass and beads as described above.One word of caution: Some Externally glazed frames have Glass Locks fitted to them. Glass Locks are correct angle pieces of metal that are inserted into unique holder clips attached to the frame. If you get rid of the beads and see these metal clips, call a glazier as these clips can be very difficult to remove without having the correct tools.
   
    If you are not sure which system you have or are not confident sufficient to proceed with the job, call a glazier. It will be more affordable in the long run to get a person who knows what they are doing than destroying your windows.You may think of lasers as needle-like crisp beams. But the semiconductor lasers used for everything from CDs to fibre-optic broadband are more like the fuzzy, spreading beams from a flashlight.Intricate arrangements of curved mirrors or lenses are needed to tame these into usable beams, especially if they need to travel long distances. A new device that fits to the front of the laser source makes the process much simpler and more efficient.It was developed by an international research team led by Frederico Capasso at Harvard University and his graduate student Nanfang Yu. So far they can reduce the spread of a beam in one plane by 25 times.Recycled energyInstead of using lenses or mirrors, the team straps a 200-micrometer tall metallic structure, dubbed a plasmonic collimator, to the front of the laser source. At the top of the device is a horizontal slit, just 2 micrometers high.That slit is placed directly over the laser source. It is so narrow that around half the beam passing through is sharply diffracted towards the surface of the metal.