Laser marking head & marking software0 pages
Sintec Optronics Technology Pte Ltd
Sintec Optronics Technology Pte Ltd
10 Bukit Batok Cres #07-02 The Spire Singapore 658079
Tel: +65 63167112 Fax: +65 63167113
Laser Marking Heads (Laser Scanners, Scan Heads)
A whole laser marking head (or called laser scanner) consists of two scan mirrors, two
galvanometers (or called galvo-scanner
motor) & drive cards (or called driver), a
XY mount, a scanning lens (f-theta lens),
an interface card (or called D/A card), a
set of marking software and a DC power
supply.
Basics of 2-axis laser scanners
A laser beam is reflected from two scan
mirrors in turn, and directed through a
focusing lens. The mirrors are capable of high speed deflection about a rotation axis, being driven
by a galvo-scanner motor. In most cases the maximum deflection angle of the mirror is ±12.5°
(often ±10° is a safer limit) either side of the non-deflected incidence angle of 45°.
Note that, for best performance, the lens will appear to be ‘the wrong way round’ when compared
with a standard meniscus lens used in conventional
focusing of a laser beam.
Some of the design objectives in specification of 2-axis
laser scanners are:
Achievement of desired scanned field size
Maximization of scan speeds
Minimizing focused spot sizes
Lowest cost solutions
Some of the limitations to be considered are:
Quality factor Q (Q = M2) of the laser beam
Scan angle limitations
Loss of power due to beam-clipping
Physical aperture of the scanner head
Field of scan
The laser beam will be scanned over an angle θ, equal to twice the mirror deflection angle. So, the
typical scanned field might be θ=±20° in both X and Y directions. (θ=±25° would be the usual
maximum scanned field). The field size is then approximately 2Ftanθ in both X and Y.
The approximation arises because:
1) it is usually desirable to have a deliberate distortion characteristic in the scanner lens design so
that the field position is proportional to θ, not tanθ.
2) scanning in two axes produces a geometrical distortion which is unrelated to the lens properties.
Focused spot size
The lower limit on spot size ‘d’ (1/e2 intensity diameter) for a laser beam of diameter ‘D’ (1/e2) is:
URL: http://www.sintecoptronics.com E-mail: sales@sintecoptronics.com
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