Abstract: A wavelength conversion element includes a fluorescent portion in which fluorescent particles are dispersed in a binder. The fluorescent portion has a first surface and a second surface which are opposite to each other in a thickness direction and excitation light is irradiated from a second surface side. A volume density of the fluorescent particles in a first portion is higher than that in a second portion where the fluorescent portion is divided in the thickness direction into two of the first portion on a first surface side and the second portion on the second surface side. A thickness of the fluorescent portion is at least 5 times as long as an average particle size of the fluorescent particles.

Abstract: A wavelength conversion element includes a fluorescent portion in which fluorescent particles are dispersed in a binder. The fluorescent portion has a first surface and a second surface which are opposite to each other in a thickness direction and excitation light is irradiated from a second surface side. A volume density of the fluorescent particles in a first portion is higher than that in a second portion where the fluorescent portion is divided in the thickness direction into two of the first portion on a first surface side and the second portion on the second surface side. A thickness of the fluorescent portion is at least 5 times as long as an average particle size of the fluorescent particles.

Abstract: A wavelength conversion element includes a fluorescent portion in which fluorescent particles are dispersed in a binder. The fluorescent portion has a first surface and a second surface which are opposite to each other in a thickness direction and excitation light is irradiated from a second surface side. A volume density of the fluorescent particles in a first portion is higher than that in a second portion where the fluorescent portion is divided in the thickness direction into two of the first portion on a first surface side and the second portion on the second surface side. A thickness of the fluorescent portion is at least 5 times as long as an average particle size of the fluorescent particles.

Abstract: The light source apparatus includes a light source and a wavelength conversion element containing quantum rods capable of converting a first linearly polarized light from the light source into a second linearly polarized light whose wavelength is different from that of the first linearly polarized light3. The apparatus further includes a changer configured to change a polarization direction of the first linearly polarized light entering the quantum rods.

Abstract: The wavelength conversion element converts a wavelength of part of an exciting light to generate a fluorescent light and thereby generate a combined light in which the fluorescent light is combined with a non-converted light whose wavelength is the same as that of the exciting light. The element includes a fluorescent body, a binder contacting the fluorescent body, and multiple diffuser particles included in the binder. A minimum particle diameter of the multiple diffuser particles is ¼ or more and 4 times or less of a wavelength of the fluorescent light, and a ratio of a volume of the multiple diffuser particles to a total volume of the binder and multiple diffuser particles is 25% or more and 50% or less.

Abstract: A photoacoustic apparatus sets a light irradiation timing such that a subject is irradiated with pulsed light at least once within a period extending from a start timing determined on the basis of a generation timing of an R-wave in an electrocardiogram signal to a point at which a first time extending from the generation timing of the R-wave in the electrocardiogram signal to a generation timing of a T-wave in the electrocardiogram signal elapses, and sets the light irradiation timing such that the subject is not irradiated with the pulsed light in a period outside the period extending from the start timing to a point at which the first time elapses.

Abstract: A light source device includes a wavelength conversion element having a fluorescent body for converting a wavelength of light from a light source, a light condensing member for condensing light from the light source to the wavelength conversion element, the light condensing member being arranged to face a surface of the fluorescent body, and a heat conductive member having heat conductivity greater than heat conductivity of the light condensing member, wherein an area where at least a part of the fluorescent body, the heat conductive member, and the light condensing member are overlapped and in contact with each other in this order is arranged, when viewed from an optical axis direction of the light condensing member.

Abstract: An image projection apparatus includes a light modulation element, and a pixel shift unit configured to shift an optical path of light from a pixel in the light modulation element and to shift a position on a projection surface of a projection pixel formed on the projection surface by a projection optical system with the light. The pixel shift unit includes an optical element configured to shift the optical path in one direction among directions orthogonal to an optical axis from the light modulation element to the projection optical system, and a rotating unit configured to change the one direction by rotating the optical element around the optical axis.

Abstract: The light source apparatus includes a light source and a wavelength conversion element containing quantum rods capable of converting a first linearly polarized light from the light source into a second linearly polarized light whose wavelength is different from that of the first linearly polarized light 3. The apparatus further includes a changer configured to change a polarization direction of the first linearly polarized light entering the quantum rods.

Abstract: To use an object information acquiring apparatus that has: a plurality of detection elements that detect acoustic waves generated from an object irradiated with light from a light source and output electric signals; a supporting member that supports the plurality of detection elements so that the axes of directivity of at least part of the detection elements gather; an inputting unit that receives an input of a measurement condition from a user; a selecting unit that selects at least part of the plurality of detection elements in response to the measurement condition input by the user; and a processing unit that acquires property information on the inside of the object, using electric signals output from the selected detection elements.

Abstract: A light source device includes a wavelength conversion element having a fluorescent body for converting a wavelength of light from a light source, a light condensing member for condensing light from the light source to the wavelength conversion element, the light condensing member being arranged to face a surface of the fluorescent body, and a heat conductive member having heat conductivity greater than heat conductivity of the light condensing member, wherein an area where at least a part of the fluorescent body, the heat conductive member, and the light condensing member are overlapped and in contact with each other in this order is arranged, when viewed from an optical axis direction of the light condensing member.

Abstract: The birefringent filter unit includes a planar birefringent plate arranged such that the light enters the birefringent plate at an approximate Brewster's angle, a first reflecting member arranged substantially parallel to the birefringent plate to allow the light having passed through the birefringent plate to enter the birefringent plate at the approximate Brewster's angle, and a second reflecting member arranged opposite to the first reflecting member and substantially parallel to the birefringent plate, which allows the light having passed through the birefringent plate after being reflected by the first regulating member to enter the birefringent plate at the approximate Brewster's angle.

Abstract: A wavelength conversion element includes a fluorescent portion in which fluorescent particles are dispersed in a binder. The fluorescent portion has a first surface and a second surface which are opposite to each other in a thickness direction and excitation light is irradiated from a second surface side. A volume density of the fluorescent particles in a first portion is higher than that in a second portion where the fluorescent portion is divided in the thickness direction into two of the first portion on a first surface side and the second portion on the second surface side. A thickness of the fluorescent portion is at least 5 times as long as an average particle size of the fluorescent particles.

Abstract: An image projection apparatus includes a light modulation element, and a pixel shift unit configured to shift an optical path of light from a pixel in the light modulation element and to shift a position on a projection surface of a projection pixel formed on the projection surface by a projection optical system with the light. The pixel shift unit includes an optical element configured to shift the optical path in one direction among directions orthogonal to an optical axis from the light modulation element to the projection optical system, and a rotating unit configured to change the one direction by rotating the optical element around the optical axis.

Abstract: The wavelength conversion element converts a wavelength of part of an exciting light to generate a fluorescent light and thereby generate a combined light in which the fluorescent light is combined with a non-converted light whose wavelength is the same as that of the exciting light. The element includes a fluorescent body, a binder contacting the fluorescent body, and multiple diffuser particles included in the binder. A minimum particle diameter of the multiple diffuser particles is ¼ or more and 4 times or less of a wavelength of the fluorescent light, and a ratio of a volume of the multiple diffuser particles to a total volume of the binder and multiple diffuser particles is 25% or more and 50% or less.

Abstract: The birefringent filter unit includes a planar birefringent plate arranged such that the light enters the birefringent plate at an approximate Brewster's angle, a first reflecting member arranged substantially parallel to the birefringent plate to allow the light having passed through the birefringent plate to enter the birefringent plate at the approximate Brewster's angle, and a second reflecting member arranged opposite to the first reflecting member and substantially parallel to the birefringent plate, which allows the light having passed through the birefringent plate after being reflected by the first regulating member to enter the birefringent plate at the approximate Brewster's angle.

Abstract: A photoacoustic apparatus sets a light irradiation timing such that a subject is irradiated with pulsed light at least once within a period extending from a start timing determined on the basis of a generation timing of an R-wave in an electrocardiogram signal to a point at which a first time extending from the generation timing of the R-wave in the electrocardiogram signal to a generation timing of a T-wave in the electrocardiogram signal elapses, and sets the light irradiation timing such that the subject is not irradiated with the pulsed light in a period outside the period extending from the start timing to a point at which the first time elapses.

Abstract: A photoacoustic apparatus includes a light irradiation unit configured to irradiate a subject with pulsed light a plurality of times, a reception unit configured to receive photoacoustic waves generated by the plurality of times of irradiation of the subject with the pulsed light from the light irradiation unit, and output a plurality of signals corresponding to the plurality of times of light irradiation, a blood information acquisition unit configured to acquire information on an amount of blood of the subject, and a subject information acquisition unit configured to acquire subject information of a target region in the subject based on the plurality of signals, wherein the subject information acquisition unit acquires the subject information based on a plurality of signals acquired in a common period in each of repeated cycles of fluctuation of the amount of blood.

Abstract: A photoacoustic apparatus according to the present invention includes an electrical stimulation unit configured to apply a voltage to a subject, and a processing unit configured to set a light irradiation timing such that the subject is irradiated with pulsed light at least once in a period from an irradiation start timing determined in accordance with an application start timing of the voltage to when a first time period starting from the application start timing and ending at an application end timing of the voltage passes, and to set the light irradiation timing such that the subject is not irradiated with pulsed light outside the period from the irradiation start timing to when the first time period passes.

Abstract: A photoacoustic apparatus according to the present invention includes an electrical stimulation unit configured to apply a voltage to a subject while light irradiation is being performed a plurality of times, and a processing unit configured to acquire, among a plurality of signals, subject information using at least part of signals corresponding to photoacoustic waves generated in a period from an extraction start timing determined in accordance with an application start timing of the voltage to when a first time period starting from the application start timing and ending at an application end timing of the voltage passes, while not using a signal corresponding to a photoacoustic wave generated outside the period from the extraction start timing to when the first time period passes.