JPH05317352A - Laser treatment device - Google Patents

Abstract

PURPOSE:To simplify the structure of a laser treatment device and decrease the amount of lowering of the internal loss of a laser resonator and the amount of deviation of an alignment by tilting a Q-switch optical member which is inserted into the laser resonator. CONSTITUTION:A laser medium rod 12 and a Q-switch pigment film 13 are disposed between the output mirror 11 and total reflection mirror 14 of a resonator and along an optical axis OP and an exciting lamp 15 is disposed over the laser medium rod 12. The Q-switch pigment film 13 is inserted at a predetermined angle theta of inclination to the optical axis OP, the predetermined angle thetabeing an of polarization. The Q-switch pigment film 13 has not only the function of a Q switch but also the function of a polarizing element to polarize light output from a pulse laser into rectilinear light. Thus the pigment film has the two functions of a Q-switch element and a polarizing element and so the structure of the laser is simplified, lowering of the internal loss of the resonator is prevented, and the amount of deviation of the alignment can be decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser treatment apparatus in which an optical member such as a Q-switch dye film has been devised for installation.

[0002]

2. Description of the Related Art A laser treatment apparatus such as a Q for eye surgery.
A laser photocoagulation surgical apparatus including a switch pulse Nd: YAG laser has a configuration as shown in FIG.

A laser medium rod 2, a Q switch dye film 3 and a polarizing element 6 are arranged between an output mirror 1 and a total reflection mirror 4, and an excitation lamp 5 is arranged in parallel with the laser medium rod 2. That is, the Q switch dye film 3 is inserted into the resonator at right angles to the optical axis OP,
By combining the Q switch dye film 3 and the polarizing element 6, a linearly polarized Q switch pulse output is obtained.

[0004]

However, when both the polarizing element 6 and the dye film 3 are inserted in the resonator, insertion loss occurs in the resonator, which adversely affects the laser output or the alignment deviation. To increase.

An object of the present invention is to provide a laser treatment apparatus in which the laser output does not decrease even when a dye film for Q switch is used and the influence of misalignment of alignment is small.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a laser treatment apparatus characterized in that a Q switch optical member to be inserted into a laser resonator is arranged at a predetermined angle. The optical member is preferably a dye film. The predetermined angle is preferably Brewster's angle.

[0007]

By tilting the Q switch optical member by a predetermined angle, a linearly polarized Q switch pulse output can be output.

[0008]

1 shows a resonator of an ophthalmic Q switch pulse Nd: YAG laser treatment apparatus which is a preferred embodiment of the laser treatment apparatus of the present invention.

The resonator has an output mirror 11 and a total reflection mirror 14, and a laser medium rod 12 and a Q switch dye film 13 are arranged between the output mirror 11 and the total reflection mirror 14 along an optical axis OP. Has been done. An excitation lamp 15 is arranged on the laser medium rod 12. The Q switch dye film 13 has a predetermined angle θ with respect to the optical axis OP.
It is tilted and placed or inserted. This predetermined angle θ
Is preferably Brewster's angle, for example about 57 degrees.

The Q-switch dye film 13 has not only a Q-switch function but also a function of a polarizing element for linearly polarizing the pulse laser output light.

The Q switch dye film 13 is, for example, a saturable absorption dye film. The dye film 13 for Q switch is arranged in the optical resonator as shown in FIG. When pumping begins, the dye film is opaque and no lasing occurs. Eventually, when the population inversion becomes sufficiently large and fluorescence begins to appear, it becomes transparent rapidly, which means that the optical switch has worked, and the Q value is easily increased rapidly to oscillate to obtain a single giant pulse. .

The present invention is not limited to the above embodiment.

[0013]

According to the present invention, the dye film has two functions of the Q switch element and the polarizing element, and does not require both the dye film and the polarizing element as in the conventional case. Therefore, the structure is simplified, the loss inside the resonator is prevented from lowering, and the alignment deviation is reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a resonator of a preferred embodiment of a laser treatment apparatus according to the present invention.

FIG. 2 is a diagram showing a resonator of a conventional laser treatment apparatus.

[Explanation of symbols]

11 Output Mirror 12 Laser Medium Rod 13 Dye Film for Q Switch (Optical Member for Q Switch) 14 Total Reflection Mirror 15 Excitation Rod OP Optical Axis ◆

Claims (3)

[Claims] 1. A laser treatment apparatus, wherein an optical member for a Q switch, which is inserted into a laser resonator, is arranged at a predetermined angle. 2. The laser treatment apparatus according to claim 1, wherein the optical member is a dye film. 3. The laser treatment apparatus according to claim 1, wherein the predetermined angle is Brewster's angle.