GB2259603A - Diode pumped solid-state laser - Google Patents
Diode pumped solid-state laser Download PDFInfo
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- GB2259603A GB2259603A GB9218740A GB9218740A GB2259603A GB 2259603 A GB2259603 A GB 2259603A GB 9218740 A GB9218740 A GB 9218740A GB 9218740 A GB9218740 A GB 9218740A GB 2259603 A GB2259603 A GB 2259603A
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/106—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity
- H01S3/108—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity using non-linear optical devices, e.g. exhibiting Brillouin or Raman scattering
- H01S3/109—Frequency multiplication, e.g. harmonic generation
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- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/0602—Crystal lasers or glass lasers
- H01S3/0606—Crystal lasers or glass lasers with polygonal cross-section, e.g. slab, prism
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- H—ELECTRICITY
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- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/09—Processes or apparatus for excitation, e.g. pumping
- H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
- H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
- H01S3/0941—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a laser diode
- H01S3/09415—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a laser diode the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping
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- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/02—Constructional details
- H01S3/025—Constructional details of solid state lasers, e.g. housings or mountings
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- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/08—Construction or shape of optical resonators or components thereof
- H01S3/08054—Passive cavity elements acting on the polarization, e.g. a polarizer for branching or walk-off compensation
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- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/08—Construction or shape of optical resonators or components thereof
- H01S3/08095—Zig-zag travelling beam through the active medium
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- H—ELECTRICITY
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- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/08—Construction or shape of optical resonators or components thereof
- H01S3/081—Construction or shape of optical resonators or components thereof comprising three or more reflectors
- H01S3/0813—Configuration of resonator
- H01S3/0815—Configuration of resonator having 3 reflectors, e.g. V-shaped resonators
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- H—ELECTRICITY
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- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/09—Processes or apparatus for excitation, e.g. pumping
- H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
- H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
- H01S3/094084—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light with pump light recycling, i.e. with reinjection of the unused pump light, e.g. by reflectors or circulators
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- H—ELECTRICITY
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- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/02—Structural details or components not essential to laser action
- H01S5/022—Mountings; Housings
- H01S5/023—Mount members, e.g. sub-mount members
- H01S5/02325—Mechanically integrated components on mount members or optical micro-benches
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Abstract
A diode pumped solid-state laser (LD directly coupled solid-state laser) comprises a laser medium 3 that has a laser emitting end face 33 with Brewster angle. Accordingly, this diode pumped solid-state laser can produce linearly polarized light. The laser also has a higher harmonics generator and an output mirror (partial reflection mirror) which reflects only a fundamental laser beam wave and transmits higher harmonics. Moreover, there is provided a fixing member assembly capable of easy and exact setting up such a directly coupled solid-state laser. <IMAGE>
Description
DIODE PUMPED SOLID-STATE LASER The present invention relates to a diode
pumped solid-state laser using a laser diode (LD) as a light source for optical pumping and capable of controlling a generated polarization mode to a satisfactory extent.
The diode pumped solid-state laser is a solid- state laser using a laser diode as a light source for optical pumping and is superior in pumping efficiency (and hence laser beam oscillation efficiency), having the possibility of realizing microminiaturization. The diode pumped solidstate laser is also attracting much is attention as a technique for developing application in the information field; for example, it generates a second harmonics with a non-linear optical crystal and is thereby utilized as a light source for a magneto optic disc.
According to the prior art, a laser beam emitted from a laser diode is introduced into a solid state laser medium via a converging lens. But recentl yr for the miniaturization of a laser system, there has been proposed an LD directly coupled solid-state laser wherein a laser diode is disposed in proximity to a solid-state laser medium without a converging lens.
Figs. 20A and 20B of the accompanying drawings are a schematic plan view and a schematic side view, respectively, of such LD directly coupled solid-state laser. In these figures, the reference numeral 1 denotes a laser diode; thenumeral 2 denotes a pump beam emitted from the laser diode 1; numeral 3 denotes a solid-state laser medium; numeral 3a denotes a pumping beam entering end face of the solid-state laser medium 3; numeral 3b denotes a laser beam emitting end face of the solid-state laser medium 3; numeral 4 denotes a laser beam emitted from the solid- state laser medium; and numeral 5 denotes a partial reflection mirror. The pumping beam entering end face 3a of the solid-state laser medium 3 has a coating which is non-reflective to the pumping beam 2 and totally reflective to the laser beam 4, while the laser beam emitting end face 3b has a coating which is highly reflective to the pumping beam 2 and nonreflective to the laser beam 4. As the solid-state laser medium 3 there may be used, for example, Nd:YAG (Y3-XNdXA15012; 0 < x < 3) crystal having a length of 5 mm, a width of 2 mm and a thickness of 0.5 mm or so.
The LD directly coupled solid-state laser operates as follows. When the pumping beam 2 enters the solid-state laser medium 3 through the pumping beam entering end face 3a, it is absorbed while being internally reflected repetitively by the upper and lower surfaces of the solid-state laser medium 3, thereby pumping the laser medium 3 effectively. The optically pumped area in the laser medium 3 extends about 0.5 mm in both vertical and parallel directions.
In this diode pumped solid-state laser, a stable type resonator is formed between the pumping beam entering end face 3a of the solid-state laser medium 3 and the partial reflection mirror 5. For example. in this stable resonatorr when the pumping beam entering end face 3a is a plane (infinite radius of curvature), the radius of curvature of the partial reflection mirror 5 is 1000 mm and the length of resonator is 10 mm, there is generated a beam having a diameter of about 0.35 mm in a basic mode (Gauss mode).
In such conventional diode pumped solid-state laser, however. the generated beam is apt to become an elliptically polarized light and it is impossible to - 3 control the polarization to a satisfactory extent. In the case where a nonlinear crystal for harmonic generation (or wavelength changing element) is inserted into the resonator to generate a higher harmonics, it is necessary to insert polarization control elements such as a polarizer and a retardation plate in the resonator, thus causing drawbacks such as a complication of apparatus construction and difficulty of assembly._ As to actually assembling this diode pumped solid-state laser while maintaining, for example, the distance between the LD and the solid-state laser medium appropriate, there has been made no concrete proposal yet.
The present invention has been accomplished in view of the above-mentioned circumstances and it is an object of the invention to provide a diode pumped solid state laser capable of easily controlling the polarization of a generated beam.
It is another object of the present invention to provide a diode pumped solid-state laser which permits easy assembly and adjustment.
- 4 It is a further object of the present invention to provide a diode pumped solid-state laser which, in the case of incorporating a higher harmonics generating element therein to generate a higher harmonic laser beam, can prevent variations in the output of the higher harmonic laser beam caused by temperature changes and permits easy monitoring of the said laser beam output, and which can attain the reduction in size-of the entire laser system even with the higher harmonic 10 generating element incorporated therein.
According to the present invention, for achieving the aforementioned objects, there is provided a diode pumped solid-state laser comprising a laser diode for generating a pumping beam, a solid-state laser medium having a section which is sufficiently small relative to the spread of the pumping beam, and a laser resonator structure for emitting a laser beam from the solid-state laser medium, characterized in that an end face on a laser beam emitting side of the solid-state laser medium has a Brewster angle relative to an optical axis of the emitted laser beam.
Further, according to another aspect of the present invention, there is provided a diode pumped solid-state laser including a laser diode for generating a pumping beam, a - 5 solid-state laser medium having a section which is sufficiently small relative to the spread of the pumping beam, a laser resonator for emitting a laser beam from the solid-state laser medium, and a higher harmonic generating element disposed in the laser resonator, an optical axis of the laser beam and that of the pumping beam being substantially coaxial with each other, to generate a higher-harmonic laser beam, characteriz-ed in that the solid-state laser medium has a pumping beam entering end face perpendicular to the laser beam and having a total reflection coating formed thereon, and also has an opposite end face opposed to the pumping beam entering end face and having a Brewster angle relative to the optical axis of the emitted laser beam; and the laser resonator is constituted by a total reflection mirror or a total reflection coating applied to the higher harmonic generating element, the total reflection coating applied to the solid-state laser medium and an output mirror which turns back a fundamental wave and outputs higher harmonics to the exterior.
Further, according to another aspect of the present invention, there is provided a diode pumped solid-state laser including a laser diode for generating a pumping beam, a 6 - solid-state laser medium having a section which is sufficiently small relative to the spread of the pumping beam, a laser resonator for emitting a laser beam from the solid-state laser medium, and a higher harmonic generating element disposed in the laser resonator, an optical axis of the laser beam and that of the pumping beam being substantially coaxial with each other, to generate a higher harmonic laser beam, characterized in that the solid-state laser medium has a pumping beam entering end face perpendicular to the laser beam and having a total reflection coating formed thereon, and also has an opposite end face opposed to the pumping beam entering end face and having a Brewster angle relative to the optical axis of the emitted laser beam; the laser resonator is constituted by a selective reflection mirror or a selective reflection coating applied to the higher harmonic generating element, which totally reflects a fundamental wave and totally or partially transmits higher harmonics, as well as the total reflection coating applied to the solid-state laser medium and an output mirror which turns back a fundamental wave and outputs higher harmonics to the exterior; and a detector for detecting the transmitted higher harmonic beam is disposed outside the laser - 7 resonator and outside the selective reflection mirror or the selective reflection coating.
According to another aspect of the present invention, moreaver, there is provided a diode pumped solid-state laser including a laser diode for generating a pumping beam, a solid-state laser medium having a section which is sufficiently small relative to the spread of the pumping beam, and a laser resonator for emitting a laser beam, the laser resonator being constituted by a pumping beam entering end face of the solid-state laser medium and an output mirror having a reflective surface opposed through the solid-state laser medium to the pumping beam entering end face of the laser medium, the pumping beam entering end face being substantially perpendicular to an optical axis of the laser beam and having a total reflection coating for the laser beam, the optical axis of the laser beam being substantially coaxial with an optical axis of the pumping beam, and the laser beam traveling straight ahead in the solid-state laser medium, characterized in that the laser diode is fixed approximately in the center of a first fixing member which is columnar; one face of the solid-state laser medium parallel to the pumping beam is fixedly bonded to a plane formed nearly in the center of a second fixing - 8 member and projecting with respect to a peripheral portion of the second fixing member, the second fixing member having a shape which covers the first fixing member; a third fixing member is provided which is cylindrical and covers the exterior of the projecting plane; and the output mirror is fixedly bonded to a fourth fixing member which is columnar and is provided with an opening in its center, the fixing members.being integral with one another so that the laser diode, the laser medium and the output mirror are in alignment with one another.
In a first aspect of the present invention, since an end face of the solid-state laser medium has a Brewster angle, an end face transmittance of p-polarized light of the emitted beam becomes maximum, so that the p-polarized light is emitted selectively.
In the second aspect of the present invention, since an end face of the laser medium which is in the form of a thin plate has a Brewster angle, the generated beam is refracted at the end face. By turning back the refracted beam with the output mirror and allowing it to be introduced into the higher harmonic generating element it is made possible to attain the reduction of size in the optical axis direction. Further, by making 9 - the reflective surface for the fundamental wave laser beam and that for higher harmonic laser beams coincident with each other, it is made possible to render higher harmonic laser beams in two directions coincident with each other in phase and optical axis, thereby preventing the occurrence of output variations and beam deviations.
In the third aspect of the present invention, a higher harmonic laser beam can be monitored easily by the higher harmonic laser beam detector disposed outside the selective reflection mirror located near the higher harmonic generating element or outside the selective reflection coating applied to the higher harmonic generating element.
In a fourth aspect of the present invention, since the solid-state laser medium is bonded onto a projecting plane, the laser medium and the bonded position are easy to see and hence the bonding work can be done easily. Moreover, since the components of the diode pumped solid-state laser are fixed each independently to a plurality of fixing members, it is easy to produce fixing members having shapes conforming to the components; besides, since the components are not rendered integral in advance, it is possible to make an optical axis edjustment easily at the time of assembly.
As a result, it becomes possible to effect a microminiaturized mounting of the diode pumped solid-state laser.
The invention will be further described by way of non-limitative example with reference to the accompanying drawings, in which:- Pigs. 1A and 1B are a schematic plan view and a schematic sectional side view of a diode pumped solidstate laser according to one embodiment of the present invention; Fig. 2 is a schematic plan view showing another embodiment of the invention; Fig. 3 is a schematic plan 7iew showing further embodiment of the invention; Fig. 4 is a schematic plan view showing still further embodiment of the invention; Fig. 5 is a schematic plan view showing still further embodiment of the invention; Figs. 6A and 6B are a schematic plan view and a schematic illustration in a crystallographic axis direction, respectively, showing still further embodiment of the invention; Fig. 7 is a schematic plan view showing still further embodiment of the invention; Fig. 8 is a schematic plan view showing still further embodiment of the invention; Fig. 9 is a schematic side view showing still further embodiment of the invention; Fig. 10 is a schematic plan view showing still further embodiment of the invention; Figs. 11A and 11B are a schematic plan view and a schematic side view, respectively, showing a_diode pumped solid-state laser according to still further embodiment of the invention;.
Fig. 12 is a schematic plan view showing a diode pumped solid-state laser according to still further embodiment of the invention; Fig. 13 is a schematic plan view showing a is diode pumped solid-state laser according to still further embodiment of the invention; Fig. 14 is a schematic plan view showing a diode pumped solid-state laser according to still further embodiment of the invention; and 20 Figs. 15A and 15B are respectively a sectional side view showing a diode pumped solid-state laser according to still further embodiment of the invention and a side view as seen from an output beam exit direction; 12 - Fig. 16 is a sectional side view showing still further embodiment of the invention; Fig. 17 is a sectional side view showing still further embodiment of the invention; Fig. 18 is a sectional side view showing still further embodiment of the invention; Fig. 19 is a sectional side view showing still further embodiment of the invention; Figs. 20A and 20B are a schematic plan view and a schematic side view, respectively, showing a conventional diode pumped solid-state laser.
Embodiments of the present invention will be described hereinunder with reference to the accompanying drawings. In connection with the drawings, members which are common to those used in preceding embodiments are indicated by the same reference numerals as in the preceding embodiments to avoid repeating explanations.
Embodiment 1:
Figs. 1A and 1B are a schematic plan view and a schematic side view, respectively, of a diode pumped solid-state laser according to embodiment 1 of the present invention.
In both figures, the numeral 1 denotes a laser diode for generating a pumping beam; numeral 2 denotes a pumping beam; numeral 3 denotes a solidstate laser medium which is, for example, Nd:YAG (Y3-XNdXA15012; 0 < x < 3) crystal of a rectangular cross section having a length of 5 mm, a width of 2 mm and a thickness of 0.5 mm; and numeral 32 denotes a pumping beam entering end face of the solid-state laser medium 3. which end -face is coated so as to be non-reflective to the pumping beam 2 and totally reflective to a.laser beam 4. Numeral 4 denotes a laser beam which is emitted from the solidstate laser medium 3; numeral 5 denotes a partial reflection mirror; and numeral 6 denotes a housing.
Numeral 33 denotes an end face of the solid- is state laser medium 3 positioned on the side opposite to the pumping beam entering side of the same laser medium. The end face 33 is cut and polished so as to have a Brewster angle in the width direction relative to the laser beam 4. It has no coating associated with reflection. In the case of Nd:YAG, the refractive index is about 1.83 and consequently the angle between the normal line of the end face 33 and an optical axis of the laser beam 4 in the laser medium is given as:
6 = tan-1 (l/1.83) = 28.7 (degree) 14 - The operation of the diode pumped solid-state laser having the above construction will be described below.
The pumping beam 2 enters the solid-state laser medium 3 through the pumping beam entering end face 32. Then, the pumping beam 2 is internally reflected repetitively by upper and lower faces 31 of the solid-state laser medium 3 and is absorbed while being confined in the laser medium, whereby the laser medium is pumped effectively.. Within the solid-state laser medium 3, the laser beam 4 travels straight ahead perpendicularly to the pumping beam entering end face 32 and is reflected, but is refracted by the laser medium end face 33, while in the air (in the housing 6) it assumes a rectilinear form at an angle of 32.60 relative to the optical axis of the laser beam 4 in the solid state laser medium 3. A stable type resonator is formed between the pumping beam entering end face 32 and the partial reflection mirror 5.
Since the end face 33 has a Brewster angle, the polarized light component (p-polarized light) of the laser beam 4 in the width direction of the solid-state laser medium 3 wholly transmits the said end face, thus permitting an efficient emission of the laser beam is without loss at the end face 33. On the other hand, as to the polarized light component (s-polarized light) in the thickness direction, the emission of the laser beam is- suppressed because of a reflectivity of 20% or more. As a result, p-polarized light can be obtained as the emitted laser beam 4 without insertion of any other optical elements. In this case, it is not necessary to use an angle adjusting mechanism for maintaining the Brewster angle because the laser beam 4 is sure to be perpendicular to the pumping beam entering end face 32. Embodiment 2:
Fig. 2 is a schematic plan view showing embodiment 2 of the present invention. In the same figure, a laser beam is allowed to travel in a zigzag fashion by utilizing a total reflection of a side face 34 of a solid-state laser medium 3. In this construction, as shown in the figure, an optical axis of a laser beam 4 can be set in parallel with the side face 34 of the solid-state laser medium 3 in the air by suitably selecting a total reflection angle for the pumping beam 2. This embodiment is also advantageous in that since the laser beam travels along a zigzag optical path, the substantial optical path length becomes longer 16 and hence the length of the solid-state laser medium 3 can be set short. Embodiment 3:
Fig. 3 is a schematic plan view showing embodiment 3 of the present invention. In the same figure, a pumping beam entering end face 32 of a solidstate laser medium 3 is formed to have a Brewster angle relative to an optical axis of a pumping beam 2, while an opposite-side end face 33 is formed to have a Brewster angle relative to an optical axis of a laser beam 4. In this construction, a reflected light of the pumping beam 2 from the pumping beam entering end face 32 is prevented from influencing the operation of the laser diode 1, whereby there can be obtained a laser which ensures a stabler operation. Embodiment 4:
Fig. 4 is a schematic plan view showing embodiment 4 of the present invention. In the same figure, an end face 51 on a solid-state laser medium 3-side of a resonator mirror (partial reflection mirror) 5a as a constituent of a resonator is cut obliquely and is disposed in such a manner that an optical axis of a laser beam 4 extends substantially along a straight line as a whole. An opposite end face 52 of the resonator 17 mirror Sa is formed with a partial reflection coating, and together with the pumping beam entering end face 32 of the solid-state laser medium 3, it constitutes a resonator. In this construction, the end face 52 of the resonator mirror 5a and the pumping beam entering end face 32 of the solidstate laser medium 3 become parallel to each other, thus facilitating the assembly of the laser beam generator. Embodiment 5:
Fig. 5 is a schematic plan view showing embodiment 5 of the present invention. In this embodiment, two solid-state laser mediums 3 and 7 are disposed so that a laser beam 4 travels along a straight line. One end face 71 of the added, solid-state laser is medium 7 has a Brewster angle to the laser beam 4, while an opposite end face 72 thereof perpendicular to the laser beam and has a non- reflective coating. According to this construction, a resonator mirror 5 and a pumping beam entering end face 32 of the solid-state laser medium 3 become parallel to each other, thus facilitating the assembly of the laser beam generator. Embodiment 6:Figs. 6A and 6B are respectively a schematic plan view and an explanatory view in a crystallographic - 18 axis direction (an end view of a higher harmonic generating element 8 as seen from the solid-state laser medium 3), showing embodiment 6 of the present invention.
In Fig. 6A there is illustrated a diode pumped solid-state laser wherein a higher harmonic generating element 8 is incorporated in a resonator to effect an efficient generation of a second harmonic wave. B-oth end faces of the higher harmonic generating element 8 has a non-reflective coating for a laser beam 4. For example, it is known (Japanese Patent Laid Open No. 220879/1989) that if Nd:YAG is used as a solid-state laser medium 3 and KTP (KTiOP04) crystal is used as the higher harmonic generating element 8, the second harmonic wave generating efficiency becomes maximum when the polarization direction of the laser beam in the resonator is at 450 to c axis of KTP. As shown in Fig. 6B, therefore, the c axis of KTP is positioned at 450 relative to upper and lower faces of the solid-state laser medium 3, it is possible to obtain a diode pumped solid-state laser capable of effecting an efficient generation of a second harmonic wave in a very simple construction. Embodiment 7:
- 19 Fig. 7 is a schematic plan view showing embodiment 7 of the present invention, in which a temperature regulator 9 is added to the higher harmonic generating element 8 used in embodiment 6. In second harmonic generation using KTP crystal, there arises an inconvenience such that a polarized light of the laser beam 4 rotates into an elliptically polarized light in the higher harmonic generating element 8, thus resulting in increased loss in the resonator.
According to this embodiment, which is for eliminating such inconvenience, the temperature of the higher harmonic generating element 8 is adjusted to change the refractive index, and the difference between an optical path length for polarized light parallel to c axis in the crystal and that for polarized light perpendicular to the c axis is set at (n + 1/2) times as long as the wavelength of the fundamental wave of the laser beam. In other words, the higher harmonic generating element 8 is a half-wave retardation plate (or 1/2 wave plate) for the fundamental wave. According to this construction, when the fundamental wave of the laser beam reciprocates through the higher harmonic generating element 8, the original polarization is preserved, without becoming spolarized light, and therefdre it is possible to perform an efficient generation of a second harmonic wave without suffering from loss at the Brewster angle. Embodiment 8:
Fig. 8 is a schematic plan view showing embodiment 8 of the present invention. This embodiment, similar to embodiment 5, is constructed in such a manner that an end face 81 of a higher harmonic generating element 8 is at a Brewster angle relative to a laser beam 4. According to this construction, a resonator mirror 5 and a pumping beam entering end face 32 of a solid-state laser medium 3 become parallel to each other, thus facilitating the assembly of the laser beam generator. In this embodiment, a non-reflective coating on the end face 81 can be omitted. Embodiment 9:
Fig. 9 is a schematic side view showing embodiment 9 of the present invention. Although in the above embodiments, an end face of the solidstate laser medium is formed to have a Brewster angle in the width direction, a Brewster angle of an end face 33 of the solid-state laser medium 3 may be set in the thickness direction as in this embodiment 9. Embodiment 10:
- 21 Although a so-called end pump type solid-state laser has been shown in each of the above embodiments wherein the optical axis of the pumping beam 2 from the laser diode 1 and that of the laser beam 4 are coincident with each other, the present invention is also applicable to a side-pump type solid-state laser wherein the optical axis of the pumping beam 2 and that of the laser beam 4 are orthogonal to each other, as shown in Fig. 10, whereby the same effects as above can be obtained. In this embodiment 10, a non-reflective coating for the pumping beam 2 is formed on a side face 34 of a solid-state laser medium 3. Embodiment ll:
Figs. 11A and 11B are a schematic plan view and a schematic side view, respectively, of a diode pumped solid-state laser according to embodiment 11 of the present invention. In the figures, the numerals 41 and 42 denote higher harmonic laser beams, and numeral 5 denotes an output mirror having a radius of curvature, say, R = 400 mm or so, the output mirror 5 being coated to totally reflect a fundamental wave laser beam and totally transmit the higher harmonic laser beams 41, 42. Numeral 8 denotes KTP crystal of a higher harmonic generating element disposed adjacent a solid-state laser 22 - medium 3. Its crystal cut-out angle is adjusted to make phase matching for the fundamental wave laser beam 4 and the higher harmonic laser beams 41, 42 in the case of incidence perpendicular to an end face 81.
In this embodiment, within a solid-state laser medium 3, the fundamental wave laser beam 4 travels straight ahead perpendicularly to a pumping beam entering end face 32, but is refracted at a laser medium end face 33, then in the air, it advances on a straight line which makes an angle of about 32.60 relative to the optical axis in the solid-state laser medium 3, and reaches the output mirror 5. The laser beam 4 is reflected by the output mirror 5 in such a manner that its advancing direction becomes substantially parallel is to the optical axis in the solid-state laser medium 3, then enters the higher harmonic generating element 8 and is totally reflected onto the original optical axis by an end face 82 of the higher harmonic generating element 8, whereby the fundamental wave laser beam 4 is confined between the pumping beam entering end face 32 of the solid-state laser medium 3 and the end face 82 of the higher harmonic generating element 8 to effect harmonic generation.
The higher harmonic laser beam output sometimes varies depending on temperature and the cause of this phenomenon is presumed to be as follows. In general manufacturing methods, it is extremely difficult to fabricate the higher harmonic generating element 8 at a thickness below the wavelength accuracy of higher harmonic laser beam. One of the two components 41 and 32 of a higher harmonic laser beam reciprocates through the higher harmonic generating element 8 and is combined with the other component generated at only one way, so that a phase shift is present unavoidably between the two. This phase shift is apt to vary due to a change of refractive index upon change of thermal conditions in the higher harmonic generating element 8 caused by a change of output level, thus resulting in interference of the two components of a higher harmonic laser beam which are output, and hence the output is not stable. Further, if the two end faces 81 and 82 of the higher harmonic generating element 8 are not formed strictly in parallel with each other, there will occur an angular deviation between the two laser beam components 41 and 42, with the result that the beam mode changes depending on the propagation distance of two spots are formed when converged.
24 - In this embodiment, in the interior of the higher harmonic generating element 8, part of the fundamental wave laser beam 4 is converted tosecond harmonic laser beams 41 and 42 having a wavelength one half that of the laser beam 4. The higher harmonic laser beam 41 is generated by conversion from the fundamental wave laser beam 4 which travels from the left to the right in the higher harmonic generating element 8 in the figures, and it is output as it is to the exterior through the output mirror 5. On the other hand, the harmonic laser beam 42 is generated by conversion from the fundamental wave laser beam 4 traveling from the right to the left in the higher harmonic generating element 8, and it is totally reflected by the end face 82 of the higher harmonic generating element 8, then advances on the same optical axis as that of the harmonic laser beam 41 and is output to the exterior through the output mirror 5. Since this construction involves a total reflection surface (end face 82) common to both the fundamental wave laser beam 4 and the harmonic laser beam 42, both harmonic laser beams 41 and 42 pass along the optical axis of the fundamental wave laser beam 4, and hence there does not occur an optical axis deviation between the two beams 41 and 42. Moreovert the fundamental wave laser beam 4 and the harmonic laser beam 42 are in same phase with each other because of phase matching of the higher harmonic generating element 8. Besides, since the end face 82 of the higher harmonic generating element 8 is a resonator end, the phase of the fundamental wave laser beam 4 and that of the harmonic laser beam 42, after reflection, coincide with each other, so that the harmonic laser beam 41 is also in same phase therewith. Consequently, the beam output resulting from combination of the two harmonic laser beams 41 and 42 is kept stable even in the event of change in various characteristics, e.g. refractive index of the higher harmonic generating element 8 caused by a change in temperature, etc.
Further, as shown in Fig. 11A, the solid-state laser medium 3 and the higher harmonic generating element 8 need not be aligned in the laser beam direction, thus permitting a great reduction in size of the whole. Embodiment 12:
Fig. 12 illustrates an embodiment wherein a non-reflective coating for the wavelength of a fundamental wave laser beam 4 and that of higher harmonic laser beams 41, 42 is formed on an end face 82 of a higher harmonic generating element 8, and a total reflection mirror 91 is disposed outside the end face 82. The total reflection mirror 91 has a total reflection coating for the wavelength of the fundamental wave laser beam 4 and that of the harmonic laser beams 41, 42.
In this construction. the fundamental wave laser beam 4 which has entered a higher harmonic generating element 8 passes through the end face 82 of the element 8 and is totally reflected onto the original optical axis by the total reflection mirror 91. whereby the laser beam 4 is confined between a pumping beam entering end face 32 of a solid-state laser medium 3 and the total reflection mirror 91 to effect harmonic generation. On the other hand, the harmonic laser beam 42 which has been generated by conversion from the fundamental wave laser beam 4 traveling from the right to the left in the higher harmonic generating element 8 is totally reflected by the total reflection mirror 91, then advances on the same optical axis as that of the harmonic laser beam 41 and is output to the exterior through an output mirror 5. According to this embodiment, there does not occur a phase shift of the harmonic laser beams, and restrictions on the - 27 fabrication accuracy for the higher harmonic generating element 8 are mitigated. Embodiment 13:
Fig. 13 illustrates an embodiment wherein an end face 33 on the side opposite to a pumping beam incidence side 32 of a solid-state laser medium 3 is cut and ground so as to have a Brewster angle in the thickness direction relative to a fundamental wave-laser beam 4. In this construction, the size of the entire apparatus in the width direction of the solid-state laser medium 3 can be reduced to the size of the solidstate laser medium 3 and the higher harmonic generating element 8 (almost to the size of each element), thus permitting a further promotion of miniaturization. Embodiment 14: Fig. 14 illustrates an embodiment wherein a selective reflection coating which is totally reflective to the wavelength of a fundamental wave laser beam 4 and non-reflective to the wavelength of higher harmonic 20 laser beams 41, 42, is formed on an end face 82 of a higher harmonic generating element 8 and a harmonic laser beam detector 10 is disposed outside the end face 82. According to this construction, the fundamental laser beam 4 which has entered the higher harmonic - 28 generating element 8 is totally reflected onto the original optical axis by the end face 82 of the higher harmonic generating element, whereby the laser beam 4 is confined between a pumping beam entering end face 32 of a solid-state laser medium and the end face 82 of the higher harmonic generating element 8 to effect harmonic generation. On the other hand, the harmonic laser beam 42 which has been generated by conversion from the fundamental wave laser beam 4 traveling from the right to the left in the higher harmonic generating element 8 passes through the end face 82 of the higher harmonic generating element 8 and reaches the harmonic laser beam detector 10. The detection surface of the detector 10 is slightly inclined lest the reflected light from the is detection surface should exert an influence on the harmonic laser beam 41. According to this embodiment, due to the presence of the detector 10, it is possible to monitor the harmonic laser beam output and also possible to collect data associated with various controls for the light source 3.
Although in this embodiment a selective reflection coating is formed on the end face 82 of the higher harmonic generating element 8, a coating which is non-reflective to the wavelength of the fundamental wave laser 4 and that of the harmonic laser beams 41, 42 may be formed on the end face 82 and a selective reflection mirror may be disposed outside the end face 82 as to detect the harmonic laser beam output.
Further, although in this embodiment a nonreflective coating for the higher harmonic laser beams is-used, there may be used a partially reflective coating, thereby allowing only part of the higher_ harmonic laser beam 42 to be detected by the harmonic laser beam detector 10. Embodiment 15:
Figs. 15A and 15B are a sectional side view and a front view, respectively, showing embodiment 11 of the present invention. In these figures, the numeral 11 denotes a first fixing member which is columnar and functions to fix a laser diode 1 and numeral 34 denotes a second fixing member for fixing a solid-state laser medium 3, with an underside 31 of the solid-state laser medium 3 being fixed to the second fixing member 34 by bonding for example. Numeral 35 denotes a jig; numeral 36 denotes a third fixing member which is cylindrical; numeral 4 denotes a laser beam emitted from the solidstate laser medium; numeral 5 denotes an output mirror; and numeral 51 denotes a fourth fixing member for fixing the output mirror 5. As shown in Fig. 15B, the outer periphery of the second fixing member 34 is rectangular, while the remainder thereof is cylindrical. The other fixing members are generally cylindrical.
A laser diode 1 is fixed to a nearly central part of the cylindrical, first fixing member 11 by soldering or bonding. The solid-state laser medium 3 is fixed by bonding to a plane formed substantially centrally of the second fixing member 34 having a shape which covers the first fixing member 11, the said plane projecting with respect to the peripheral portion. The jig 35 and the second fixing member 34 hold the first fixing member 11 therebetween and fix it while adjusting the position of the laser diode 1 and that of the solid- state laser medium 3 by utilizing threaded hales 341, 342, 343 and 344 formed in the second fixing member 34, as shown in Fig. 15B. The third fixing member 36 covers the surroundings of the foregoing projecting plane. The output mirror 5 is fixed, for example by bonding, to the fourth fixing member 51 having a central opening. These fixing members are rendered integral in a cylindrical shape as a whole using bolts or by bonding, and are assembled so that the laser diode 1, laser medium 3 and output mirror 5 are aligned on a single straight line.
A pumping beam 2, which is incident from a pumping beam entering end face 32, is internally reflected repetitively by upper and lower faces 31 of the solid-state laser medium 3 and is absorbed while being confined in the laser medium 3, thereby pumping the laser medium 3 effectively. By allowing the light which spreads in the vertical direction of the laser diode active layer to be reflected by upper and lower faces 31, there is obtained an optically pumped area of about 0.5 mm in both vertical and parallel directions in the solid-state laser medium 3. A stable type resonator is formed between the pumping beam entering end face 32 and the output mirror 5, and for example if the pumping beam entering end face 32 is a plane, the radius of curvature of the output mirror 5 is 400 mm and the resonator length is 10 mm, there is generated a beam of about 0.25 mm in diameter in the basic mode (Gauss mode).
Although in the above embodiment the outer peripheral portion of the second fixing member 34 is made rectangular, it may be circular. Further, the entire shape is generally cylindrical in the above embodiment, the same effects as above are attained even if the entire shape is made prismatic.
- 32 Embodiment 16:
Fig. 16 illustrates an embodiment in which the fixing of a solid-state laser medium 3 is performed using both a fifth fixing member 37 and a fixing bolt 38. In this embodiment, the fifth fixing member 37 which is pressed down by the fixing bolt 38 pushes a solid-state laser medium 3 uniformly against a plane formed on a second fixing member 34. By using a material superior in thermal conductivity as the material of the second and fifth fixing members 34, 37, it is made possible to effect uniform cooling from the upper and lower faces of the solid-state laser medium 3 and it is possible to remove a thermal strain of the laser medium 3 and obtain a laser beam superior in converging property. Further, the replacement of the solid-state laser medium 3 can be done easily by loosening the fixing bolt 38. Embodiment 17:
Fig. 17 illustrates an embodiment in which the third and fourth fixing members 36, 51 used in the embodiment 1 of Fig. 1 are rendered integral with each other. This embodiment is advantageous in that the number of constituent parts is decreased and the assembly is easy.
- 33 Embodiment 18:
Fig. 18 illustrates an embodiment in which a higher harmonic generating element is provided within a resonator to realize the generation of a second harmonic wave. In this embodimentr a non-linear crystal for harmonic generation (or higher harmonic generating element) 8 is fixed in the interior of a fourth fixing member 51 by means of a sixth fixing member 81 and-a fixing bolt 82. According to this construction, there is obtained a laser light source for second harmonic generation which is compact in shape and can be assembled easily.
Although in this embodiment the higher harmonic generating element 8 is fixed to the fourth fixing member 51, a fixing member for only the higher harmonic generating element 8 may be separately provided. In this case, the higher harmonic generating element 8 and the output mirror 5 can be adjusted for their optical axes independently.
Although in this embodiment the higher harmonic generating element 8 is fixed using the sixth fixing member 85 and the fixing bolt 86, it may be fixed using an adhesive or the like.
Embodiment 19:
Fig. 19 illustrates an embodiment in which, in addition to the embodiment of Fig. 14. a quarter-wave retardation plate (or 1/4 wave phase plat) is disposed in the interior of the resonator. In this embodiment, a 1/4 wave phase plate 75 is fixed to a seventh fixing member 71 using an adhesive for example, the seventh fixing member 71 being made integral with the other fixing members 36, 51 using bolts or by bonding. -In the case where the higher harmonic generating element 8 is KTP (KTiOP04) crystal, as disclosed in Japanese Patent Laid Open No. 220879/89, it is possible to obtain a higher harmonic generating laser which provides a stable output, by setting the crystallographic axis of the phase plate 75 at 450 relative to the crystallographic axis (c axis) of the higher harmonic generating element 8.
As set forth above, since the diode pumpe solid-state laser of the present invention is constructed so that an end face of a laser medium has a Brewster angle relative to the laser optical axis, it is possible to obtain a linearly polarized laser beam efficiently without the use of any additional polarization controlling element. Besidesf the number of components required becomes smaller and it is not - 35 necessary to use en angle adjusting mechanism for maintaining the Brewster angle, thus facilitating the assembly of the apparatus.
Further, according to the present invention, an end face of a solid-state laser medium opposed to a pumping beam entering end face of the laser medium is formed to have a Brewster angle relative to the optical axis of emitted laser beam, and a laser resonator is constituted by a total reflection mirror or a total reflection coating applied to a higher harmonic generating element, a total reflection coating formed on the pumping beam entering end face and an output mirror which turns back a fundamental wave and outputs higher harmonics to the exterior, allowing beam refracted at a laser medium end face to be turned back by the output mirror and introduced into the higher harmonic generating element. Consequently, it is possible to attain the reduction of size in the optical axis direction. Moreover, since the fundamental wave laser beam reflecting surface and the higher harmonic laser beam reflecting surface are made coincident with each otherr higherharmonic laser beams traveling in two directions coincide in phase and optical axis with each 36 - other, thus preventing the occurrence of output variation and beam deviation.
Further. the end face of the solid-state laser medium opposed to the pumping beam entering end face of the laser medium is formed to have a Brewster angle relative to the optical axis of emitted laser beam; a laser resonator is constituted by a selective reflection mirror or a selective reflection coating applied t_o the higher harmonic generating element, which totally reflects a fundamental wave and totally or partially transmits higher harmonics, a total reflection coating formed on the pumping beam entering end face of the laser medium and an output mirror which turns back the fundamental wave and outputs the higher harmonics to the is exterior; and a harmonic laser beam detector is disposed outside the selective reflection mirror or the selective reflection coating applied to the higher harmonic generating element. Consequently, it is possible to monitor the harmonic laser beam output easily.
According to the present invention, moreover, a laser diode is fixed nearly in the center of a first fixing member which is columnar; one of surfaces of a solid-state laser medium parallel to a pumping beam is fixed by bonding to a plane formed approximately - 37 centrally of a second fixing member having a shape of covering the first fixing member, the said plane projecting with respect to the peripheral portion; the exterior of the projecting plane is covered with a third fixing member; an output mirror is fixed by bonding to a fourth fixing member which is columnar and has a central opening; and the fixing members are rendered integral so that the laser diode, the laser medium and the output mirror are aligned with one another. Consequently, the 10 laser medium and its bonded position are easy to see, thus facilitating the positioning and bonding work for the laser medium. Moreover, since the constituent parts of the diode pumped slid-state laser are fixed each independently to the fixing members, it is possible to is easily fabricate fixing members of shapes matching the constituent parts. At the time of assembly, moreover, it is easy to make optical axis adjustment because the fixihg members are not integral, and it is possible to adjust the position of a laser diode and that of a solid-state laser medium, so as to achieve an efficient incidence of a pumping beam from a pumping beam entering end face of the solid-state laser medium. It is also easy to make optical axis adjustment and assembly of an - 38 output mirror, etc. and there can be obtained a smallsized, diode pumped solid-state laser.
The present invention is not limited to the above embodiments. It will be obvious to those skilled in the art that various changes and modifications may be made within the scope of the appended claims.
39 -
Claims (13)
1. A diode pumped solid-state laser comprising a laser diode for generating a pumping beam, a solid-state laser medium having a section which is sufficiently small relative to the spread of the pumping beam, and a laser resonator structure for emitting a laser beam from the solidstate laser medium, wherein an end face on the laser beam emitting side of said solidstate laser medium is formed to have a Brewster angle relative to an optical axis of the emitted laser beam.
2. A diode pumped solid-state laser according to claim 1, wherein the optical axis of the laser beam and that of the pumping beam are substantially coaxial with each other.
3. A diode pumped solid-state laser according to claim 1 or 2, wherein said solid-state laser medium has a pumping beam entering end face perpendicular to the laser beam and having a total reflection coating formed thereon, and the laser beam travels straight ahead in the solidstate laser medium.
4. A diode pumped solid-state laser according to claim 1 or 2, wherein said solid-state laser medium has a pumping beam entering end face perpendicular to the - laser beam and having a total reflection coating formed thereon, and the laser beam travels in a zigzag fashion in the solid-state laser medium while utilizing a total reflection at a side face of the solid-state laser medium.
5. A diode pumped solid-state laser according to claim 1, 2, 3 of 4, wherein said pumping beam entering end face of the solid-state laser medium has a Brewster angle relative to the optical axis of the pumping beam for the wavelength of the pumping beam.
6. A diode pumped solid-state laser according to claim 1, wherein the optical axis of the laser beam and that of the pumping beam are substantially perpendicular to each other.
7. A diode pumped solid-state laser according to arry one of the preceding claims, wherein a higher harmonic generating element is disposed within the resonator.
8. A diode pumped solid-state laser according to claim 7, wherein an end face of said higher harmonic generating element has a Brewster angle relative to the optical axis of the laser beam.
9. A diode pumped solid-state laser according to claim 7 or 8, wherein the temperature of said higher harmonic generating element is adjusted so that the 41 - higher harmonic generating element serves as a 1/2 wave plate.
10. A diode pumped solid-state laser according to claim 1 or 2 including a higher harmonic generating element disposed in said laser resonator, to generate a higher harmonic laser beam, wherein said solid-state laser medium has a pumping beam entering end face perpendicular to the laser beam and having a total reflection coating formed thereon, and said laser resonator is constituted by a total reflection mirror or a total reflection coating applied to said higher harmonic generating element, said total reflection coating applied to said solid-state laser medium and an output mirror which turns back a fundamental wave and outputs higher harmonics to the exterior.
11. A diode pumped solid-state laser according to claim 1 or 2 including a higher harmonic generating element disposed in said laser resonator, to generate a higher harmonic laser beam, wherein said solid-state laser medium has a pumping beam entering end face perpendicular to the laser beam and having a total reflection coating formed thereon, said laser resonator is constituted by a selective reflection mirror or a selective reflection coating applied to said higher harmonic generating element, which totally reflects a fundamental wave and totally or partially transmits higher harmonics, as well as said total reflection coating applied to said solid-state laser medium and an output mirror which turns back a fundamental wave and outputs higher harmonics to the exterior; and a detector for detecting the transmitted higher harmonic beam is disposed outside said laser resonator and outside said selective reflection mirror or said selective reflection coating.
12. A diode pumped solid-state laser including a laser diode for generating a pumping beam, a solid-state laser medium having a section which is sufficiently small relative to the spread of the pumping beam, and a laser resonator for emitting a laser beam, said laser resonator being constituted by a pumping beam entering end face of said solid-state laser medium and an output mirror having a reflective surface opposed through the solid-state laser medium to said pumping beam entering end face of the laser medium, said pumping beam entering end face being substantially perpendicular to afi optical axis of the laser beam and having a total reflection coating for the laser beam, the optical axis of the laser beam being substantially coaxial with an opticalaxis of the pumping beam, and the laser beam travelling straight ahead in said solidstate laser medium, wherein said laser diode is fixed nearly in the center of a first fixing member which is columnar; one of faces of said solid-state laser medium parallel to the pumping beam is fixed by bonding to a plane formed nearly in the center of a second fixing member and projecting with respect to a peripheral portion of the second fixing member, the second fixing member having a shape which covers the first fixing member; a third fixing member is provided which is cylindrical and covers the exterior of said projecting plane; and said output mirror is fixed by bonding to a fourth fixing member which is columnar and is provided with an opening in its center, said fixing members being rendered integral with one another so that said laser diode, said laser medium and said output mirror are in alignment with one another.
13. A diode pumped solid-state laser constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 19 of the accompanying drawings.
- 44
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22666691A JPH0567824A (en) | 1991-09-06 | 1991-09-06 | Semiconductor excitation solid-state laser |
| JP6086092A JPH05267756A (en) | 1992-03-18 | 1992-03-18 | Semiconductor exciting solid laser |
| JP7117892A JP3024349B2 (en) | 1992-03-27 | 1992-03-27 | Semiconductor pumped solid-state laser |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9218740D0 GB9218740D0 (en) | 1992-10-21 |
| GB2259603A true GB2259603A (en) | 1993-03-17 |
| GB2259603B GB2259603B (en) | 1995-07-19 |
Family
ID=27297311
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9218740A Expired - Fee Related GB2259603B (en) | 1991-09-06 | 1992-09-04 | Diode pumped solid-state laser |
Country Status (2)
| Country | Link |
|---|---|
| DE (1) | DE4229545A1 (en) |
| GB (1) | GB2259603B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1994024734A1 (en) * | 1993-04-21 | 1994-10-27 | The Commonwealth Of Australia | Diode pumped slab laser |
| AU679519B2 (en) * | 1993-04-21 | 1997-07-03 | Commonwealth Of Australia, The | Diode pumped slab laser |
| US5748664A (en) * | 1994-05-06 | 1998-05-05 | The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Solid state laser with positive thermal lens |
| EP2312706A1 (en) * | 2008-07-30 | 2011-04-20 | Hamamatsu Photonics K.K. | Solid-state laser device |
| US8743917B2 (en) | 2009-12-14 | 2014-06-03 | Panasonic Corporation | Wavelength conversion light source, optical element and image display device |
| CN104205528A (en) * | 2012-03-19 | 2014-12-10 | 三菱电机株式会社 | Laser device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3824492A (en) * | 1972-06-22 | 1974-07-16 | United Aircraft Corp | Solid state single frequency laser |
| US4167712A (en) * | 1978-01-31 | 1979-09-11 | The United States Of America As Represented By The Secretary Of The Navy | Praseodymium blue-green laser system |
| US4713822A (en) * | 1985-05-24 | 1987-12-15 | Amada Engineering & Service Co., Inc. | Laser device |
| US4918703A (en) * | 1989-04-21 | 1990-04-17 | General Electric Company | Slab geometry laser material with concave edges |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2243822A1 (en) * | 1972-09-07 | 1974-03-14 | Licentia Gmbh | LASER ARRANGEMENT FOR GENERATING HARMONICS WITH LOW REFLECTION LOSS |
| US4809291A (en) * | 1984-11-26 | 1989-02-28 | Board Of Trustees, Of Leland Stanford Jr U. | Diode pumped laser and doubling to obtain blue light |
| US4656635A (en) * | 1985-05-01 | 1987-04-07 | Spectra-Physics, Inc. | Laser diode pumped solid state laser |
| US4710940A (en) * | 1985-10-01 | 1987-12-01 | California Institute Of Technology | Method and apparatus for efficient operation of optically pumped laser |
| US4987575A (en) * | 1987-12-04 | 1991-01-22 | Alfano Robert R | Tetravalent chromium (Cr4+) as a laser-active ion for tunabale solid-state lasers |
| US4933947A (en) * | 1988-02-18 | 1990-06-12 | Amoco Corporation | Frequency conversion of optical radiation |
| US5159605A (en) * | 1990-01-19 | 1992-10-27 | Mitsubishi Denki Kabushiki Kaisha | Semiconductor-laser-pumped, solid-state laser |
-
1992
- 1992-09-04 GB GB9218740A patent/GB2259603B/en not_active Expired - Fee Related
- 1992-09-04 DE DE4229545A patent/DE4229545A1/en not_active Ceased
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3824492A (en) * | 1972-06-22 | 1974-07-16 | United Aircraft Corp | Solid state single frequency laser |
| US4167712A (en) * | 1978-01-31 | 1979-09-11 | The United States Of America As Represented By The Secretary Of The Navy | Praseodymium blue-green laser system |
| US4713822A (en) * | 1985-05-24 | 1987-12-15 | Amada Engineering & Service Co., Inc. | Laser device |
| US4918703A (en) * | 1989-04-21 | 1990-04-17 | General Electric Company | Slab geometry laser material with concave edges |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1994024734A1 (en) * | 1993-04-21 | 1994-10-27 | The Commonwealth Of Australia | Diode pumped slab laser |
| AU679519B2 (en) * | 1993-04-21 | 1997-07-03 | Commonwealth Of Australia, The | Diode pumped slab laser |
| US5651021A (en) * | 1993-04-21 | 1997-07-22 | The Commonwealth Of Australia | Diode pumped slab laser |
| US5748664A (en) * | 1994-05-06 | 1998-05-05 | The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Solid state laser with positive thermal lens |
| EP2312706A1 (en) * | 2008-07-30 | 2011-04-20 | Hamamatsu Photonics K.K. | Solid-state laser device |
| EP2312706A4 (en) * | 2008-07-30 | 2013-06-26 | Hamamatsu Photonics Kk | Solid-state laser device |
| US8743917B2 (en) | 2009-12-14 | 2014-06-03 | Panasonic Corporation | Wavelength conversion light source, optical element and image display device |
| CN104205528A (en) * | 2012-03-19 | 2014-12-10 | 三菱电机株式会社 | Laser device |
| CN104205528B (en) * | 2012-03-19 | 2017-03-15 | 三菱电机株式会社 | Laser device |
Also Published As
| Publication number | Publication date |
|---|---|
| DE4229545A1 (en) | 1993-05-13 |
| GB2259603B (en) | 1995-07-19 |
| GB9218740D0 (en) | 1992-10-21 |
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| Date | Code | Title | Description |
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| 746 | Register noted 'licences of right' (sect. 46/1977) |
Effective date: 19960611 |
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| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20040904 |