JP4730612B2 - Optical pickup device - Google Patents

Description

  The present invention relates to an optical pickup device capable of forming an image on a label surface of an optical disc.

  In recent years, optical discs such as CDs and DVDs have become widespread as information recording media. The CD includes a reproduction-only CD-ROM, a recordable CD-R, a rewritable CD-RW, and the like. As the DVD, a reproduction-only DVD-ROM, a recordable DVD-R, and a rewritable DVD- There are RAM, DVD-RW, and the like. A recordable optical disk, that is, a recordable or rewritable optical disk has an information recording layer, and the recording capacity of the information recording layer is, for example, about 700 MB for a CD-R and about 4.7 GB for a DVD-R or the like. .

  Particularly in recent optical pickup devices, the reproduction of information recorded on an optical disk and the shortening of the wavelength of a laser light source used as a light source for recording information on the optical disk have progressed, for example, a blue-violet semiconductor laser, Laser light sources with wavelengths of 400 to 420 nm, such as blue SHG lasers that perform wavelength conversion of infrared semiconductor lasers using second harmonics, are being put into practical use. When these blue-violet laser light sources are used, when an objective lens having the same numerical aperture (NA) as that of a DVD (digital versatile disk) is used, it is possible to record information of 15 to 20 GB on an optical disk having a diameter of 12 cm. When the NA of the objective lens is increased to 0.85, 23 to 25 GB of information can be recorded on an optical disk having a diameter of 12 cm. Hereinafter, in this specification, an optical disk and a magneto-optical disk using a blue-violet laser light source are collectively referred to as a “high density optical disk”.

By the way, a user writes a character, an image, or the like indicating the content on a label surface opposite to the information recording layer side of the optical disc and saves it. On the other hand, an optical disc and an optical pickup device have been developed that can record characters and images desired by a user on a label surface using laser light (see Patent Document 1).
JP 2005-346746 A

  However, according to the optical pickup device disclosed in Patent Document 1, laser light for recording an optical disk is focused on a label surface using an objective lens, and characters and images are formed there. The structure of the optical pickup device can be simplified. However, since a light source, an objective lens, and the like that irradiate laser light are also used for information recording / reproduction, it is not necessarily suitable for forming an image on a label surface. In particular, while the focused spot diameter at the time of recording / reproducing in the information pit is about several μm, it is desirable to have a spot diameter of about several tens of μm when characters or images are formed on the label surface. The light intensity may be insufficient.

  The present invention has been made in view of the problems of the prior art, and an object thereof is to provide an optical pickup device capable of forming an appropriate spot on a label surface.

The optical pickup device according to claim 1 includes a light source and a condensing optical system including an objective lens, and a light beam emitted from the light source is transmitted through the objective lens to the first optical information recording medium. And an optical pickup device for recording and / or reproducing information by focusing on the information recording surface of the second optical information recording medium,
When the light beam applied to the information recording surface of the first optical information recording medium passes through the optical surface of one of the optical elements of the condensing optical system at a position away from the optical axis by a predetermined distance. Does not limit the aperture, and when the light beam irradiated to the information recording surface of the second optical information recording medium passes, an aperture limiting region is provided to limit the aperture,
When the information recording surface of the second optical information recording medium is irradiated with a light beam, the light beam that has passed through the optical surface other than the aperture restriction region and is emitted from the objective lens is information on the second optical information recording medium. A light beam condensed on the recording surface to form a spot for recording and / or reproducing information and passing through the aperture limiting region and emitted from the objective lens is recorded on the second optical information recording medium. When it is focused on the surface, it does not form a spot for recording and / or reproducing information,
When the light beam is irradiated onto the label surface of the second optical information recording medium, the light beam emitted from the objective lens through an optical surface other than the aperture restriction region and the objective lens passing through the aperture restriction region A spot for forming an image is formed on the label surface by superimposing the luminous flux emitted from the label. Here, the “label surface” is a surface formed on the side opposite to the information recording surface in the optical information recording medium, and means a surface having a photosensitive layer on which characters and images can be formed by irradiating a light beam. . Such a photosensitive layer is described in, for example, JP-A-2006-31937. The term “overlapping” includes both complete overlapping and partial overlapping.

  The present inventors paid attention to the diffractive structure of an objective lens commonly used in a so-called compatible optical pickup device. In order to overcome the difference in numerical aperture NA when using interchangeably, such a diffractive structure flares a light beam that passes outside the numerical aperture NA (here, the aperture limiting region) when using an optical disc lower than a high-density optical disc, for example. In many cases, it has an aperture limiting function for emitting light. However, when the same objective lens is used to irradiate the label surface with a light beam, if the light beam that has passed through the aperture restriction region can be used to form characters or images on the label surface, the light can be effectively used. It will be.

  That is, according to the present invention, when the light beam is irradiated on the label surface of the second optical information recording medium, the light beam that has passed through the optical surface other than the aperture restriction region and is emitted from the objective lens, and the aperture restriction By superimposing the luminous flux that has passed through the region and emitted from the objective lens, a spot for forming an image is formed on the label surface, so that the light intensity of the luminous flux for forming characters and images can be improved. A clearer character or image can be formed. The aperture restriction region is not limited to the objective lens, and may be provided in any one of the optical elements of the condensing optical system.

  According to a second aspect of the present invention, in the optical pickup device according to the first aspect of the invention, the light source includes a light beam having a first wavelength λ1 and a light beam having a second wavelength λ2 longer than the first wavelength λ2. The protective layer thickness t1 of the first optical information recording medium is smaller than the thickness t2 of the protective layer of the second optical information recording medium. A diffraction structure is formed in the aperture limiting region, and when recording and / or reproducing information on the information recording surface of the second optical information recording medium, the wavelength that has passed through the aperture limiting region A feature of the present invention is that aperture restriction is performed on the light flux of λ2.

The element having the aperture restriction region has a light beam in the second polarization state when a light beam in the first polarization state and a light beam in a second polarization state different from the first polarization state are incident. It may be a polarization selective element which exhibits an aperture limiting function only to the second when recording and / or reproducing information for the information recording surface of the optical information recording medium, the aperture limiting region Aperture restriction can be performed only on the light beam having the wavelength λ2 that has passed through. As such a polarization selective element, a combination of an isotropic medium and a birefringent medium is known, and is described in, for example, Japanese Patent Application Laid-Open No. 2006-12391. Regarding the selection of the first polarization state and the second polarization state in the incident light of the objective lens, an element capable of switching the polarization state in the condensing optical system (for example, when switching the polarization direction as an example of the polarization state, This can be dealt with by inserting a liquid crystal element capable of electrically switching the polarization direction, a mechanism for mechanically rotating the wave plate, or by selectively blinking light sources having different polarization directions of the emitted light beam.

According to a third aspect of the present invention, there is provided the optical pickup device according to the first or second aspect , wherein the first optical information recording medium is a BD (Blu-ray Disc).

According to a fourth aspect of the present invention, there is provided the optical pickup device according to the first or second aspect , wherein the first optical information recording medium is an HD DVD.

According to a fifth aspect of the present invention, in the optical pickup device according to the third or fourth aspect , the second optical information recording medium is a DVD.

According to a sixth aspect of the present invention, there is provided the optical pickup device according to any one of the first to fifth aspects, wherein a light beam having a wavelength λ3 (λ3> λ2) emitted from a third light source is applied to the condensing optical system. through it, characterized in that intends line recording and / or reproducing information by focused on the information recording surface of the third optical information recording medium of thickness t3 of the protective layer (t3> t2).

According to a seventh aspect of the present invention, in the optical pickup device according to the sixth aspect of the present invention, the third optical information recording medium is a CD.

  ADVANTAGE OF THE INVENTION According to this invention, the optical pick-up apparatus which can form an appropriate spot on a label surface can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram schematically showing a configuration of an optical pickup apparatus PU1 of the present embodiment that can appropriately record and / or reproduce information on BD, DVD, and CD, which are different optical disks. Such an optical pickup device PU1 can be mounted on an optical information recording / reproducing device. Here, the first optical information recording medium is BD, the second optical information recording medium is DVD, and the third optical information recording medium is CD. The present invention is not limited to the present embodiment.

  The optical pickup device PU1 is used for a blue-violet semiconductor laser LD1 (first light source) and a DVD that emits a 408 nm blue-violet laser beam (first beam) when recording / reproducing information on a BD. A red semiconductor laser LD2 (second light source) that emits light and emits a 658 nm laser beam (second beam) when information is recorded / reproduced with respect to the light source packages LDP and CD formed in one package. An infrared semiconductor laser LD3 (third light source) that emits a 785 nm laser beam (third beam) when recording / reproducing information and a photodetector that receives a reflected beam from the information recording surface RL3 of the CD Common detector PD1 for hololasers HL, BD and DVD composed of PD2 (may have a plurality of light receiving parts for BD and DVD), one group structure Single-lens objective lens (objective optical element) OL made of polyolefin plastic, 2-axis actuator AC1, 1-axis actuator AC2, and a single-axis actuator arranged in a common optical path through which the first to third light beams pass in common A beam expander EXP, a first polarizing beam splitter BS1, a second polarizing beam splitter BS2, and a λ / 4 wavelength plate QWP, each of which includes a first lens L1 and a second lens L2 that can be shifted in the optical axis direction from AC2. A sensor lens SEN for adding astigmatism to the reflected light beam from the information recording surface RL1, and disposed in an optical path through which the first light beam and the second light beam pass, so that the first light beam and the second light beam are converted into parallel light beams. The first collimator COL1 to be converted and the second collimator which is disposed in the optical path through which only the third light beam passes and converts the third light beam into a parallel light beam. And COL2. In addition to the blue-violet semiconductor laser LD1 described above, a blue-violet SHG laser can also be used as a light source for BD. The coupling lens through which the first light beam passes, that is, the first collimator COL1, preferably has a diffractive structure having a function of correcting chromatic aberration on the optical surface. The light source package LDP and the holo laser HL constitute a light source. The first collimator COL1, the second collimator COL2, the beam expander EXP, and the objective lens OL constitute a condensing optical system.

  As shown in FIG. 2, in the objective lens OL according to the present embodiment, a central region CN including the optical axis on the aspherical optical surface on the light source side, a peripheral region MD disposed around the central region CN, and a periphery thereof Are formed concentrically with the optical axis as the center. Note that a diffractive structure to be described later is formed in the central region CN, the peripheral region MD, and the outermost peripheral region OT.

  When recording / reproducing information with respect to the BD in the optical pickup device PU1, the position of the first lens L1 in the optical axis direction so that the first light beam is emitted from the beam expander EXP in a parallel light beam state. Is adjusted by the single-axis actuator AC2, and the blue-violet semiconductor laser LD1 is caused to emit light. The divergent light beam emitted from the blue-violet semiconductor laser LD1 is reflected by the first polarization beam splitter BS1 and then converted into a parallel light beam by the collimator COL1 as depicted by the solid line in FIG. The diameter is expanded by EXP, passes through the λ / 4 wave plate QWP, the diameter of the light beam is regulated by a diaphragm (not shown), and enters the objective lens OL in the state of parallel light, and then passes through the protective substrate PL1 of the BD from there. This is a spot formed on the recording surface RL1. A focused spot is formed on the information recording surface RL1 of the BD by the light beam that has passed through the central area CN, the peripheral area MD, the most peripheral area OT, and the optical surface on the optical disc side of the objective lens OL. The objective lens OL is driven for focusing and tracking by a biaxial actuator AC1 arranged in the periphery thereof.

  The reflected light beam modulated by the information pits on the information recording surface RL1 is transmitted again through the objective lens OL, the λ / 4 wave plate QWP, the beam expander EXP, and the second polarizing beam splitter BS2, and then converted into a converged light beam by the first collimator COL1. Then, after passing through the first polarizing beam splitter BS1, astigmatism is added by the sensor lens SEN and converges on the light receiving surface of the photodetector PD1. And the information recorded on BD can be read using the output signal of photodetector PD1.

  Further, when information is recorded / reproduced with respect to the DVD in the optical pickup device PU1, the optical axis direction of the first lens L1 is emitted so that the second light flux is emitted from the beam expander EXP in the state of a parallel light flux. Is adjusted by the single-axis actuator AC2, and then the red semiconductor laser LD2 is caused to emit light. The divergent light beam emitted from the red semiconductor laser LD2 is reflected by the first polarization beam splitter BS1 and then converted into a parallel light beam by the collimator COL1, as depicted by the dotted line in FIG. 1, and the beam expander EXP. The diameter of the light beam passes through the λ / 4 wavelength plate QWP, the light beam diameter is regulated by a diaphragm (not shown), and enters the objective lens OL in the state of parallel light, and from there, the information is recorded through the protective substrate PL2 of the DVD. This is a spot formed on the surface RL2. A focused spot, that is, a spot center portion is formed on the information recording surface RL2 of the DVD by the light flux that has passed through the central area CN, the peripheral area MD, and the optical surface on the optical disc side of the objective lens OL. The light flux that has passed through the outermost peripheral region OT is flared to form a spot peripheral portion. The objective lens OL is driven for focusing and tracking by a biaxial actuator AC1 arranged in the periphery thereof.

  The reflected light beam modulated by the information pits on the information recording surface RL2 is transmitted again through the objective lens OL, the λ / 4 wave plate QWP, the beam expander EXP, and the second polarizing beam splitter BS2, and then converted into a converged light beam by the first collimator COL1. Then, after passing through the first polarizing beam splitter BS1, astigmatism is added by the sensor lens SEN and converges on the light receiving surface of the photodetector PD1. And the information recorded on DVD can be read using the output signal of photodetector PD1.

  Further, when information is recorded / reproduced with respect to the CD in the optical pickup device PU1, the first lens L1 is set so that the third light beam is emitted from the beam expander EXP in the state of weakly divergent light beam or parallel light beam. After the position in the optical axis direction is adjusted by the uniaxial actuator AC2, the infrared semiconductor laser LD3 is caused to emit light. The divergent light beam emitted from the infrared semiconductor laser LD3 is converted into a parallel light beam by the second collimator COL2, as illustrated in FIG. Thereafter, the light is reflected by the second polarizing beam splitter BS2 and is changed to a weakly divergent light beam by the beam expander EXP, or is expanded in diameter while being a parallel light beam, and then passes through the λ / 4 wavelength plate QWP to reach the objective lens OL. After entering in the state of weak finite diverging light or parallel light, it becomes a spot formed on the information recording surface RL3 from there through the protective substrate PL3 of the CD. A focused spot, that is, a spot center portion is formed on the information recording surface RL3 of the CD by the light beam that has passed through the central region CN of the objective lens OL and the optical surface on the optical disc side. The light flux that has passed through the most peripheral area OT and the peripheral area MD is flared to form a spot peripheral portion. The objective lens OL is driven for focusing and tracking by a biaxial actuator AC1 arranged in the periphery thereof.

  The reflected light flux modulated by the information pits on the information recording surface RL3 is again transmitted through the objective lens OL, the λ / 4 wavelength plate QWP, and the beam expander EXP, and then reflected by the second polarization beam splitter BS2, and is reflected by the second collimator COL2. Converted to convergent luminous flux. Then, it converges on the photodetector PD2. And the information recorded on CD can be read using the output signal of photodetector PD2.

  When the first light beam emitted from the blue-violet semiconductor laser LD1 enters the objective optical element OL, the first diffractive structure in the central region CN, the second diffractive structure in the peripheral region MD, and the third diffractive structure in the most peripheral region OT. Can appropriately correct the spherical aberration of the first light flux and appropriately record and / or reproduce information on the BD having the thickness t1 of the protective substrate. Further, when the second light beam emitted from the red semiconductor laser LD2 is incident on the objective lens OL, the first diffractive structure in the central region CN and the second diffractive structure in the peripheral region MD are the thicknesses of the protective substrates of the BD and DVD. The spherical aberration of the second light beam generated due to the difference in thickness and the difference in wavelength between the first light beam and the second light beam is appropriately corrected, and the most peripheral area OT causes the second light beam to flare on the information recording surface of the DVD. Therefore, it is possible to appropriately record and / or reproduce information on a DVD having a protective substrate thickness t2. Further, when the third light beam emitted from the infrared semiconductor laser LD3 is incident on the objective optical element OL, the first diffractive structure in the central region CN is different in the thickness difference between the BD and CD protective substrates and the first light beam. The spherical aberration of the third light beam generated due to the difference between the wavelength of the third light beam and the third light beam is appropriately corrected, and the second diffractive structure of the peripheral region MD and the outermost peripheral region are transferred to the third light beam on the information recording surface of the CD. Due to the flare, information can be recorded and / or reproduced appropriately for a CD having a protective substrate thickness t3. Further, since the first diffraction structure in the central region CN has a good diffraction efficiency of the third light beam used for recording / reproduction, it is possible to obtain a light amount of the third light beam sufficient for recording / reproduction. In addition, the second diffractive structure of the peripheral region MD has a spherochromatism (chromatic spherical aberration) when the wavelength of the first light flux and the second light flux deviates from the reference wavelength due to a laser manufacturing error or the like. ) Or a spherical aberration that occurs with a temperature change when a temperature change occurs.

  Next, image formation on the label surface will be described. In the optical pickup device PU1, when an image is formed on the label surface of the optical disc, the label surface of the optical disc is set toward the objective lens side, and the light expander EXP is used as a weakly divergent beam or a parallel beam. After the position of the first lens L1 in the optical axis direction is adjusted by the uniaxial actuator AC2 so that three light beams are emitted, the infrared semiconductor laser LD3 is caused to emit light. The divergent light beam emitted from the infrared semiconductor laser LD3 is converted into a parallel light beam by the second collimator COL2, as illustrated in FIG. Thereafter, the light is reflected by the second polarizing beam splitter BS2 and is changed to a weakly divergent light beam by the beam expander EXP, or is expanded in diameter while being a parallel light beam, and then passes through the λ / 4 wavelength plate QWP to reach the objective lens OL. After entering in the state of weak finite divergent light or parallel light, the label surface is irradiated from there and becomes a spot formed on the label surface. In the present embodiment, the light flux that has passed through the peripheral region MD and the most peripheral region OT (here, the aperture limiting region) of the objective lens OL does not become flare light, but the central region CN (here, the region other than the aperture limiting region). Since the light beam that passes through and is superimposed on the light beam that becomes a condensing spot on the label surface, a spot having a higher light intensity can be formed in addition to the light beam that has passed through the central region CN. A desired image can be formed by repeatedly turning the spot on and off while rotating the optical disk.

  The reflected light beam reflected from the label surface again passes through the objective lens OL, the λ / 4 wavelength plate QWP, the beam expander EXP, and the second polarizing beam splitter BS2, and then is converged to a first light beam by the first collimator COL1. After passing through the polarization beam splitter BS1, astigmatism is added by the sensor lens SEN and converges on the light receiving surface of the photodetector PD1. A clear image can be formed by performing focusing and tracking of the objective lens OL by using the output signal of the photodetector PD1.

  For example, the red semiconductor laser LD2 may be used to form an image on the label surface, or when the label surface is formed with a photosensitive layer whose color changes according to the wavelength, the blue-violet semiconductor laser LD1 A cyan component is formed using the light beam, a magenta component is formed using the light beam of the red semiconductor laser LD2, and a yellow component is formed using the infrared semiconductor laser LD3, thereby forming a full-color image on the label surface. You can also

FIG. 3 is a simulation diagram showing the spot light SP and the flare light FL on the information recording surface when the CD is used. From this, it can be seen that the flare light FL is irradiated around the spot light SP . FIG. 4 is a longitudinal spherical aberration diagram of the spot light on the information recording surface when using the CD. From this, it can be seen that the spherical aberration increases in the peripheral region and the aperture limiting function is exhibited.

  FIG. 5 is a simulation diagram in which spot light and flare light on the label surface are superimposed when image formation is performed on the label surface, and shows a state in which spherical aberration is the smallest. FIG. 6 is a simulation diagram showing only flare light on the label surface under the same conditions as in the example shown in FIG. 3, 5, and 6, the spot light and flare light are separated during CD recording / reproduction, but the light intensity of the spot light increases by superimposing the flare light on the spot light when forming the image on the label surface. I understand that

  FIG. 7 is a simulation diagram showing the spot light and flare light superimposed on the label surface when forming an image on the label surface. The objective lens is moved closer to the optical disk side by 50 μm from the state where the spherical aberration is the smallest. State. FIG. 8 is a simulation diagram showing only flare light on the label surface under the same conditions as in the example shown in FIG. For example, as shown in FIGS. 5 to 8, the objective lens is moved in the optical axis direction within the range of 0 to 100 μm with respect to the objective lens position where the spherical aberration of the spot condensed on the label surface is minimized. By doing so, the spot diameter on the label surface can be increased and the amount of flare light taken into the spot can be increased.

  The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate. For example, the present invention may be an optical pickup device compatible with HD DVD / DVD / CD, an optical pickup device compatible with BD / DVD, or an optical pickup device compatible with HD DVD / DVD. There may be.

It is a figure which shows schematically the structure of optical pick-up apparatus PU1 of this Embodiment which can record and / or reproduce | regenerate information appropriately with respect to BD, DVD, and CD which are different optical disks. It is sectional drawing of the objective lens OL concerning this Embodiment. It is a simulation figure which shows spot light SP and flare light FL on the information recording surface at the time of CD use. It is a longitudinal spherical aberration diagram in the spot light on the information recording surface when using the CD. FIG. 5 is a simulation diagram showing spot light and flare light superimposed on a label surface when an image is formed on the label surface. It is a simulation figure which shows only the flare light on a label surface on the same conditions as the example shown in FIG. FIG. 5 is a simulation diagram showing spot light and flare light superimposed on a label surface when an image is formed on the label surface. It is a simulation figure which shows only the flare light on a label surface on the same conditions as the example shown in FIG.

Explanation of symbols

AC1 2-axis actuator AC2 1-axis actuator BS1 1st polarization beam splitter BS2 2nd polarization beam splitter CN Central region COL1 1st collimator COL2 2nd collimator EXP Beam expander FL Flare light HL Holo laser L1 1st lens L2 2nd Lens LD1 Blue-violet semiconductor laser LD2 Red semiconductor laser LD3 Infrared semiconductor laser LDP Light source package MD Peripheral area OL Objective lens OT Most peripheral area PD1 First photodetector PD2 Second photodetector
SP spot light PL1 Protective substrate PL2 Protective substrate PL3 Protective substrate PU1 Optical pickup device QWP λ / 4 wavelength plate RL1 Information recording surface RL2 Information recording surface RL3 Information recording surface SEN Sensor lens

Claims (7)

An optical recording system including a light source and a condensing optical system including an objective lens, and recording a light beam emitted from the light source on the first optical information recording medium and the second optical information recording medium via the objective lens An optical pickup device that records and / or reproduces information by focusing on a surface,
When the light beam applied to the information recording surface of the first optical information recording medium passes through the optical surface of one of the optical elements of the condensing optical system at a position away from the optical axis by a predetermined distance. Does not limit the aperture, and when the light beam irradiated to the information recording surface of the second optical information recording medium passes, an aperture limiting region is provided to limit the aperture,
When the information recording surface of the second optical information recording medium is irradiated with a light beam, the light beam that has passed through the optical surface other than the aperture restriction region and is emitted from the objective lens is information on the second optical information recording medium. A light beam condensed on the recording surface to form a spot for recording and / or reproducing information and passing through the aperture limiting region and emitted from the objective lens is recorded on the second optical information recording medium. When it is focused on the surface, it does not form a spot for recording and / or reproducing information,
When the light beam is irradiated onto the label surface of the second optical information recording medium, the light beam emitted from the objective lens through an optical surface other than the aperture restriction region and the objective lens passing through the aperture restriction region A spot for forming an image on the label surface is formed by superimposing the luminous flux emitted from the optical pickup device.   The light source selectively emits a light beam having a first wavelength λ1 and a light beam having a second wavelength λ2 longer than the first wavelength λ2, and the light source of the first optical information recording medium The thickness t1 of the protective layer is smaller than the thickness t2 of the protective layer of the second optical information recording medium, and a diffraction structure is formed in the aperture limiting region, and the second optical information recording 2. The aperture restriction is performed on the light beam having the wavelength λ2 that has passed through the aperture restriction region when information is recorded and / or reproduced on the information recording surface of the medium. The optical pickup device described. The optical pickup device according to claim 1 or 2 , wherein the first optical information recording medium is a BD (Blu-ray Disc). The optical pickup device according to claim 1 or 2, wherein the first optical information recording medium is HD DVD. The optical pickup device according to claim 3 or 4, wherein the second optical information recording medium is DVD. Information recording on a third optical information recording medium having a thickness t3 (t3> t2) of the protective layer is applied to the light beam having the wavelength λ3 (λ3> λ2) emitted from the third light source via the condensing optical system. the optical pickup device according to any one of claims 1 to 5, characterized in that intends line recording and / or reproducing information by converging the surface. The optical pickup device according to claim 6 , wherein the third optical information recording medium is a CD.

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