A protection device for an Optical Emission Spectrometer (OES) and a method of protecting a detector to which purge gas is supplied, in an OES, are disclosed. The protection device comprises a timer, which measures a parameter, such as a humidity value, indicative of a shut down time period following cessation of application of purge gas to the detector. The protection device comprises a processor, which determines a start-up time period, based on the parameter, during which purge gas is supplied to the detector prior to cooling of the detector. The processor may selectively trigger commencing or maintaining application of purge gas to the detector or cooling of the detector in dependence on the parameter.

A protection device for an Optical Emission Spectrometer (OES) and a method of protecting a detector to which purge gas is supplied, in an OES, are disclosed. The protection device comprises a timer, which measures a parameter, such as a humidity value, indicative of a shut down time period following cessation of application of purge gas to the detector. The protection device comprises a processor, which determines a start-up time period, based on the parameter, during which purge gas is supplied to the detector prior to cooling of the detector. The processor may selectively trigger commencing or maintaining application of purge gas to the detector or cooling of the detector in dependence on the parameter.

A testing device (10) for testing the level of a selected chemical in central heating system water in a central heating system circuit comprises: a sample chamber (14) for holding a sample of central heating system water to be tested, the sample chamber (14) being connectable (12) to the central heating system circuit to allow fluid to pass between the central heating system circuit and the sample chamber (14); means (16) for controlling filling of the sample chamber (14) with central heating system water from the central heating system circuit, and emptying of the sample chamber (14); at least one valve (18) for isolating the sample of central heating system water from the heating circuit during testing; and optical testing apparatus including a light source (20) and a detector (22), for measuring an optical property of the sample of central heating system water isolated within the sample chamber (14) and thereby making a determination as to whether or not the level of the selected chemical in the water is greater than a predetermined threshold level.

A testing device (10) for testing the level of a selected chemical in central heating system water in a central heating system circuit comprises: a sample chamber (14) for holding a sample of central heating system water to be tested, the sample chamber (14) being connectable (12) to the central heating system circuit to allow fluid to pass between the central heating system circuit and the sample chamber (14); means (16) for controlling filling of the sample chamber (14) with central heating system water from the central heating system circuit, and emptying of the sample chamber (14); at least one valve (18) for isolating the sample of central heating system water from the heating circuit during testing; and optical testing apparatus including a light source (20) and a detector (22), for measuring an optical property of the sample of central heating system water isolated within the sample chamber (14) and thereby making a determination as to whether or not the level of the selected chemical in the water is greater than a predetermined threshold level.

A detector includes a light source configured to emit measurement light, a flow cell incorporating a cell channel through which a sample solution flows inside, a photodetector configured to detect light from the flow cell, an optical system configured to guide light from the light source to the flow cell and guide light from the flow cell to the photodetector, and a flow cell accommodating part configured to cover the flow cell so as to spatially separate the flow cell from the optical system. Of the side surfaces of the flow cell accommodating part, the side surfaces facing the light incident surface and the light exit surface of the flow cell are formed from wall surfaces made of a light transmissive material, or sealed by a light transmissive plate material.

An optical system may include an objective lens system having a primary optical axis and a relay lens system having a relay optical axis. The relay optical axis may have a first angular offset with respect to the primary optical axis. The objective lens system may be configured to provide light from a light source to the relay lens system and provide light from the relay lens system to an image sensor. The relay lens system may be configured to provide light from the objective lens system to an end face of an optical fiber, where the end face has a second angular offset with respect to a cross-sectional axis of the optical fiber. The relay lens system may provide light reflected from the end face to the objective lens system.

An optical system may include an objective lens system having a primary optical axis and a relay lens system having a relay optical axis. The relay optical axis may have a first angular offset with respect to the primary optical axis. The objective lens system may be configured to provide light from a light source to the relay lens system and provide light from the relay lens system to an image sensor. The relay lens system may be configured to provide light from the objective lens system to an end face of an optical fiber, where the end face has a second angular offset with respect to a cross-sectional axis of the optical fiber. The relay lens system may provide light reflected from the end face to the objective lens system.

A system is presented for evaluating grain in a grain handling system. The system includes a sensor system and a sample conveyor system. In one or more arrangements, the sensor system is operatively connected to the grain handling system and includes an optical sensor. The sample conveyor system is configured to collect samples of grain in the grain handling system, deliver the samples of grain to the sensor system, and remove the samples of grain from the sensor system. The sensor system is configured to measure characteristics of the samples of grain delivered to the sensor system by the sample conveyor system. In one or more arrangements, the system includes a cleaning system configured to clean the optical sensor, the lens; and/or other components of the sensor system. In one or more arrangements, the system includes a recalibration system configured to recalibrate the optical sensor.

A test device includes a specimen a specimen with a circular cross section that accommodates a test target, a specimen holding part that has an opening with a circular cross section and holds the specimen, a plurality of light emitting elements that irradiate the specimen with light from a plurality of directions, a light-receiving element that faces the light emitting elements through the specimen, and a pressing member that projects from an interior wall of the opening into the opening to press the specimen and press the specimen against the interior wall on an opposite side.

A test device includes a specimen a specimen with a circular cross section that accommodates a test target, a specimen holding part that has an opening with a circular cross section and holds the specimen, a plurality of light emitting elements that irradiate the specimen with light from a plurality of directions, a light-receiving element that faces the light emitting elements through the specimen, and a pressing member that projects from an interior wall of the opening into the opening to press the specimen and press the specimen against the interior wall on an opposite side.