A water quality analyzer for analyzing sample water. The water quality analyzer includes an excitation light irradiating optical system configured to irradiate the sample water with first light, a component in the sample water being excited by the first light to emit fluorescence, a scattered light irradiating optical system configured to irradiate the sample water with second light, the second light being scattered by microparticles in the sample water to form the scattered light, a fluorescence detecting optical system configured to detect a portion of the second light that has passed through the sample water, and to detect the emitted fluorescence, and a scattered light detecting optical system configured to detect a portion of the first light that has passed through the sample water, and to detect the scattered light.

Various turbidimeters are described that can detect light directly in a substantially circular, e.g., encompassing, manner such that an increased amount of scattered light from a sample vial may be detected by a light detector, e.g., a photodiode or photodiode array. In an embodiment, a substantially circular photodiode array is provided to directly detect scattered light in an arc about the sample vial. In other embodiments, light guides are provided in an arc element that guides light to a detector or detectors. Other aspects are described and claimed.

A cleaning robot has an optical measuring device for determining the type of surface to be cleaned. The optical measuring device has a light source and at least two light sensors. Light emitted by the light source hits a reflection point of the surface at an angle of incidence (), and is reflected to the first light sensor at a corresponding angle of reflection (). The light source, reflection point and first light sensor span a plane of incidence. A secondary plane that intersects the reflection point and has a second light sensor spans perpendicular to the surface, and exhibits an angle () of between 80 and 100 relative to the plane of incidence. A straight line running through the reflection point and second light sensor has an angle () relative to the surface that is essentially as large as the angle of incidence () or angle of reflection ().

A method for measuring turbidity, chlorine content and color of a liquid, the method including retaining, from a continuous flow of the liquid, a sample volume of the liquid, and at least nearly simultaneously executing at least two of detecting illumination from the sample volume of liquid by at least a first detector operable for detecting illumination from the sample volume of liquid at a 90-degree angle with respect to an illumination beam generated by an illuminator and impinging on the sample volume of liquid, thereby measuring a turbidity of the sample volume of liquid.

A method of and apparatus (18) are described for assessing fat in whey in the making of a dairy product in accordance with a dairy product recipe. The method comprises the steps of: a. using one or more optical sensors (61, 62, 63, 64) to sense at least one stream (22, 24, 27, 29) of whey separated from curd in dairy product making apparatus (18) and generate one or more signals indicative of the degree of occlusion of the stream (22, 24, 27, 29) of whey; b. converting or processing one or more said signals as a measure of the specific mass of fat lost from curd in a dairy product making plant (18) in the stream of whey; c. assessing whether the value of specific mass of fat lost obtained in Step b lies within or outside a predetermined fat loss range; and d. if the said value of specific mass of fat lost is outside the predetermined range, adjusting the recipe so that the value of specific mass of fat lost lies within the predetermined range.

Disclosed is a cell analyzer that includes a flow cell through which a measurement specimen containing a body fluid flows, a light emission unit that applies light onto the measurement specimen flowing through the flow cell, a light detection unit that detects forward scattered light generated from cells in the measurement specimen to which the light is applied, an analysis unit that is programmed to analyze the cells in the body fluid based on a forward scattered light signal detected by the light detection unit, and an output unit. The analysis unit is programmed to control the output unit to output information about tumor cells in the body fluid, based on forward scattered light signal intensity and forward scattered light signal width.

A light intensity measurement system includes a light source unit configured to emit coherent light to aqueous humor of a subject eye, a polarization control unit that is arranged between the light source unit and the subject eye, and configured to control a polarization state of the coherent light, and a measurement unit configured to measure light intensity of scattered light in the aqueous humor of the coherent light. With this configuration, a light intensity measurement system that can non-invasively measure the concentration of substances contained in aqueous humor of a subject eye is provided.

A method for detecting a contamination of a cuvette of a turbidimeter. The turbidimeter includes a light source which emits a light beam directed to a cuvette, a scattering light detector, and a diffuser with a body and an actuator. The actuator moves the body between a parking position and a test position where the body is between the measurement light source and the cuvette, thereby interferes with the light beam, and generates a diffuse test light entering the cuvette. The method includes activating the actuator to move the body from the parking position into the test position, activating the light source, measuring a test light intensity received by the scattering light detector, comparing the test light intensity measured with a reference light intensity, and generating a contamination signal if a difference between a reference light intensity and the test light intensity measured exceeds a first threshold value.

A dynamic light scattering apparatus includes a source configured for irradiating a sample with primary electromagnetic radiation, a detector configured for detecting secondary electromagnetic radiation generated by scattering the primary electromagnetic radiation at the sample, a refraction index determination unit including a movable optical element and configured to determine information indicative of a refraction index of the sample based on measurements of the secondary electromagnetic radiation for a plurality of different positions of the movable optical element, and a particle size determining unit configured to determine information indicative of particle size of particles in the sample by analyzing the detected secondary electromagnetic radiation and taking into account the refraction index determined by the refraction index determining unit.

A water quality analyzer for analyzing sample water. The water quality analyzer includes an excitation light irradiating optical system configured to irradiate the sample water with first light, a component in the sample water being excited by the first light to emit fluorescence, a scattered light irradiating optical system configured to irradiate the sample water with second light, the second light being scattered by microparticles in the sample water to form the scattered light, a fluorescence detecting optical system configured to detect a portion of the second light that has passed through the sample water, and to detect the emitted fluorescence, and a scattered light detecting optical system configured to detect a portion of the first light that has passed through the sample water, and to detect the scattered light.