A spectroscopic measuring device includes a halogen lamp as a light source, a lens of an irradiating system, a mirror, and a spectrometer. The lens of the irradiating optical system emits light from the halogen lamp to a measurement object. The mirror is an optical member, and the mirror is arranged coaxial with the lens and conducts detecting light between the halogen lamp and the measurement object, to the spectrometer. The spectrometer is an analyzing part and analyzes material of the measurement object on the basis of the light received via the mirror. The light from the halogen lamp to the measurement object passes through the peripheral part of the optical axis of the lens, and the light to be received by the spectrometer passes through the center part of the optical axis of the lens, at the position of the mirror.

Devices and methods for detecting particulate matter are described herein. One device includes a laser, a reflector, an ellipsoidal reflector, and a detector, wherein the laser is configured to emit a beam, the reflector is configured to reflect the beam toward the ellipsoidal reflector, and the ellipsoidal reflector has a first focal region located on a path of the reflected beam, and a second focal region located at a surface of the detector.

A droplet sensor includes an optical cover having an ellipsoid surface that is a portion of a spheroid, a light source disposed at or in proximity to a first focal point of the ellipsoid surface, and a light detector disposed at or in proximity to a second focal point of the ellipsoid surface. The ellipsoid surface includes an effective detection area configured to reflect light emitted by the light source toward the light detector, and an amount of light reflected by the effective detection area changes in accordance with adhesion of droplets on the ellipsoid surface. The optical cover includes a space having a hemispherical surface, the space being centered at the second focal point. The hemispherical surface includes a transmission scattering surface on a region that receives the light reflected by the effective detection area.

A droplet sensor includes: an optical cover having an ellipsoid surface that is a portion of a spheroid; a light source disposed at or in proximity to a first focal point of the ellipsoid surface; and a light detector disposed at or in proximity to a second focal point of the ellipsoid surface, wherein the ellipsoid surface is an effective detection area configured to reflect light emitted from the light source toward the light detector, and an amount of light reflected by the effective detection area changes in accordance with adhesion of droplets on the ellipsoid surface, and wherein the optical cover has a curved surface that is tangentially connected to an outside of the effective detection area and having a curvature greater than a curvature of the ellipsoid surface.

A system for measuring thermal degradation of composites includes a cylindrical body; a bottom cover having a lower central aperture; an upper concave mirror facing the bottom cover with an upper central orifice concentric with a central axis of the body; a lower concave mirror facing the upper concave mirror with a lower central orifice concentric with the central axis; a source of actinic radiation between the upper concave mirror and the lower concave mirror on the central axis to direct actinic radiation through the lower central orifice and lower central aperture; and a camera with an image sensor positioned concentrically relative to the upper central orifice; wherein the bottom cover is adjustable relative to the cylindrical body to provide a focusing function for the image sensor by varying the distance from the lower central orifice and the upper reflective surface.

High numerical aperture collection optics for particle analyzers may include an ellipsoidal reflector or an ellipsoidal reflector in combination with a spherical reflector, and may efficiently collect light scattered or emitted by particles in a sample stream and then couple that collected light into a lower numerical aperture portion of the instrument's optical detection system, such as into an optical fiber for example. The reflectors may be integrated with a flow cell through which the sample stream passes, or may be separate components arranged around a flow cell or, in instruments not employing a flow cell, arranged around a sample stream in air. Refractive beam steering optics may allow multiple closely spaced excitation beams to be directed into the sample stream at low angles of incidence. The collection optics and refractive beam steering optics may be employed separately or in combination with each other.

The gas detection apparatus comprises a figure of all or a part of n ellipsoids. When a region inside the ellipsoid E.sub.i and not including the ellipsoid E.sub.si is defined as a region R.sub.i, the ellipsoid E.sub.i including a light source region of the light emitting part is defined as an ellipsoid E.sub.s, the ellipsoid E.sub.i including a light receiving region of the light receiving part is defined as an ellipsoid E.sub.d, the region R.sub.i of the ellipsoid E.sub.s is defined as a region R.sub.in, and the region R.sub.i of the ellipsoid E.sub.d is defined as a region R.sub.out, 60% or more of the light source region is present in the region R.sub.in and 60% or more of the light receiving region is present in the region R.sub.out.

A particle detector formed by a body defining a chamber and housing a light source and a photodetector. A reflecting surface is formed by a first reflecting region and a second reflecting region that have a respective curved shape. The curved shapes are chosen from among portions of ellipsoidal, paraboloidal, and spherical surfaces. The first reflecting region faces the light source and the second reflecting region faces the photodetector. The first reflecting region has an own first focus, and the second reflecting region has an own first focus. The first focus of the first reflecting region is arranged in an active volume of the body, designed for detecting particles, and the photodetector is arranged on the first focus of the second reflecting region.

In an embodiment a beam-guiding cavity structure includes at least one first curved surface, one second curved surface and one third curved surface spanning a cavity, the first-third curved surfaces respectively having at least one first focal point and one second focal point, wherein the cavity is configured such that substantially no distance is laterally formed between the first focal point of the first curved surface and the second focal point of the second curved surface, wherein the cavity is further configured such that substantially no distance is laterally formed between the first focal point of the second curved surface and the second focal point of the third curved surface, wherein the first focal point of the second curved surface is arranged next to a connecting line of the first and second focal points of the first curved surface, wherein the first focal point of the third curved surface is arranged next to a connecting line of the first and second focal points of the second curved surface, and wherein the first, second and third curved surfaces have different shapes or dimensions to one another.

Certain configurations are described herein of an optical spectrometer and instruments including an optical spectrometer. In some instances, the optical spectrometer is configured to spatially separate provided wavelengths of light to permit detection or imaging of each provided wavelength of light. Improved sensitivities and detection limits may be achieved using the optical spectrometers described herein.