Abstract: The present invention realizes an enhancement of a fabrication yield and a reduction of a size regarding an optical modulator or an optical device including polarization beam combining means. An optical modulator of the present invention (1) includes: first and second optical modulators (LN optical modulators (101) to (104)) that are formed on a substrate; a polarization beam rotating unit (107) that rotates at least one polarization beam of modulated light beams modulated by the first and second optical modulators; and a polarization beam combining element (110) that is disposed outside the substrate and that combines the polarization beams of the modulated light of which the polarization beams are rotated by the polarization beam rotating unit (107).

Abstract: The present invention realizes an enhancement of a fabrication yield and a reduction of a size regarding an optical modulator or an optical device including polarization beam combining means. An optical modulator of the present invention (1) includes: first and second optical modulators (LN optical modulators (101) to (104)) that are formed on a substrate; a polarization beam rotating unit (107) that rotates at least one polarization beam of modulated light beams modulated by the first and second optical modulators; and a polarization beam combining element (110) that is disposed outside the substrate and that combines the polarization beams of the modulated light of which the polarization beams are rotated by the polarization beam rotating unit (107).

Abstract: A laser beam generating apparatus includes a semiconductor element and a second harmonic generating element that performs a wavelength conversion on fundamental light emitted from the semiconductor element, the laser beam generating apparatus is an external resonance-type laser diode that has an external resonator structure and emits a transversal single mode laser beam, and the second harmonic generating element is a waveguide-type second harmonic generating element that includes a single mode waveguide.

Abstract: A laser beam generating apparatus includes a semiconductor element and a second harmonic generating element that performs a wavelength conversion on fundamental light emitted from the semiconductor element, the laser beam generating apparatus is an external resonance-type laser diode that has an external resonator structure and emits a transversal single mode laser beam, and the second harmonic generating element is a waveguide-type second harmonic generating element that includes a single mode waveguide.

Abstract: There is provided an optical resonator having good temperature characteristics, allowing mass-production, and having excellent long-term stability, and an optical resonator which constitutes a wavelength control module capable of coping with an increase in density of wavelength interval. The optical resonator has two substrates having a specified reflectance, disposed oppositely and parallel to each other through a spacer, so that the reflection surfaces become inside. The spacer is made from a material having a coefficient of linear expansion of almost zero, formed in a block with a specified thickness, and having a hollow part penetrating in the thickness direction. The hollow part communicates with the outside through a groove part, and the two substrates are joined on opposite end faces of the spacer in the thickness direction.

Abstract: A wavelength stabilization module which can restrain light reflected by the fiber grating from returning to a light source, and a stable wavelength laser beam generating device. A wavelength stabilization module of the invention comprises an optical splitter 122 for splitting light lead from a light source 110 through a fiber 143 into first and second lights, a fiber grating 210 which has light of a specific wavelength in the first light pass therethrough and reflects light of the other wavelengths in the first light, and a light quantity change operating unit 311 for detecting a change in quantity of light passing through the fiber grating using the second light as reference light, and is configured to direct light, reflected by the fiber grating 210, to the outside of the fiber, and is configured to feed back the detected change in light quantity to the light source 110.

Abstract: An optical receiver board wherein, a signal light is amplified in an optical fiber amplifier. The amplified signal light is supplied to an electrically driven optical wavelength-tuning filter such as a multi-layered film interference filter, through which a signal light of a predetermined wavelength bandwidth is transmitted. The transmitted signal light is divided into first and second signal lights. The first signal light is converted to an electric signal which is amplified by an equalizing amplifier, and an amplified electric signal is supplied to a discrimination circuit, in which an information electric signal is generated by using a timing signal. The optical wavelength-tuning filter comprises a rotation actuator having a magnet-rotating portion and control coils, and an optical filter member fixed to the top of the magnet-rotating portion.

Abstract: In order to produce a chrysoberyl single crystal displaying a luminous band effect, a mixture of a principal component consisting of beryllium oxide and aluminum oxide in nearly equal molar amounts with small amounts of titanium oxide and coloring metal oxide is sintered or melted and solidified in a non-oxidizing gas atmosphere to provide a raw material bar; the raw material bar is heated in a non-oxidizing gas atmosphere by means of a light condense-heating type floating zone method to grow a chrysoberyl single crystal; and the single crystal is heated so as to allow needle crystals of titanium oxide to be deposited in one orientation in the chrysoberyl single crystal.