The principle of laser-adjusting and the method of laser-measuring were described and applied to adjust the gaps of one model relay. A plenty of tests and measurements for adjusting relay’s springs by laser beam were finished. After data analyzed

several results were summarized and shown as follows: the laser-adjusting quantum

h

is in linear direct proportion to the distance

x

2

between measuring point and adjusting point

and the formula can be expressed by

h=kx

2

. The laser power

P

and the irradiation time

t

are approximate parabola relation curves to adjusting quantum

h

. The stronger the power

P

and the longer the irradiation time

t

the bigger the quantum

h

at the rise phase

But when it is over the inflexion

the results are opposite. The experimental results also show that there is no negative influence of laser-adjusting on the relay’s mechanical life. It is feasible for adjusting the relay’s gap by laser beam when the laser power

P

and the time

t

set equal each other. With combining the test data of the relay’s gap

it is known that the gap of the most relays on the assembly line can be adjusted correctly after adjusting the settled spring only

which will be more efficiency in comparon of laser-adjusting with manual-adjusting.