A non-destructive opto-acoustic metrology device detects the presence and location of non-uniformities in a film stack that includes a large number, e.g., 50 or more, transparent layers. A transducer layer at the bottom of the film stack produces an acoustic wave in response to an excitation beam. A probe beam is reflected from the layer interfaces of the film stack and the acoustic wave to produce an interference signal that encodes data in a time domain from destructive and constructive interference as the acoustic wave propagates upward in the film stack. The data may be analyzed across the time domain to determine the presence and location of one or more non-uniformities in the film stack. An acoustic metrology target may be produced with a transducer layer configured to generate an acoustic wave with a desired acoustic profile based on characteristics of the film stack.

A non-destructive opto-acoustic metrology device detects the presence and location of non-uniformities in a film stack that includes a large number, e.g., 50 or more, transparent layers. A transducer layer at the bottom of the film stack produces an acoustic wave in response to an excitation beam. A probe beam is reflected from the layer interfaces of the film stack and the acoustic wave to produce an interference signal that encodes data in a time domain from destructive and constructive interference as the acoustic wave propagates upward in the film stack. The data may be analyzed across the time domain to determine the presence and location of one or more non-uniformities in the film stack. An acoustic metrology target may be produced with a transducer layer configured to generate an acoustic wave with a desired acoustic profile based on characteristics of the film stack.

Method of measuring the thickness of a layer by a light source irradiating the layer with a light beam, which light source is controlled by a sinusoidal control signal having a modulation frequency f.sub.m so that the light beam presents optical power that is sinusoidally modulated at the modulation frequency, the measurement method consisting in: using detector elements to determine a calibration phase shift (Δφ.sub.cal) between the optical power and the control signal; heating the layer with the light beam; using the detector elements to detect a sinusoidal component of a heat flux radiated by the layer; calculating a phase shift (Δφ.sub.th/opt) between the sinusoidal component of the radiated heat flux and the optical power of the light beam while taking account of the calibration phase shift; and determining the thickness of the layer of material as a function of the phase shift (Δφ.sub.th/opt).

Various embodiments provide systems and methods for detecting defects in components of a fuel cell. Embodiment methods and systems for detecting a defect in an interconnect for a fuel cell system include thermally exciting the interconnect using optical radiation and/or inductive stimulation, detecting a thermal response of the interconnect, and based on the thermal response, determining the presence or absence of a defect in the interconnect, such as a lateral or through crack in the interconnect.

The present invention provides a method of measuring the placement of material forming a blow-molded plastic container after the container is released from a mold of a blow molder having a plurality of molds, wherein each plastic container comprises a continuous sidewall and a base, the method comprising the steps of: detecting with an infrared camera infrared light emitted from the container after the container is released from a mold; converting the detected infrared light into corresponding electrical signals; transmitting the electrical signals to a microprocessor; comparing in the microprocessor the electrical signals with stored data regarding desired material distribution forming the plastic container; and producing output information regarding the placement of material forming the container.

Disclosed herein are methods for estimating a powder layer thickness in an additive manufacturing machine when forming a three-dimensional article layer by layer. The method comprises applying a first powder layer and selectively melting the first powder layer and thereafter measuring the temperature of the first powder layer at a plurality of times. The method further comprises providing a mathematical function giving a reference temperature as a function of time based on the measured temperatures of the first powder layer, applying a second powder layer on top of the first powder layer and measuring the temperature of the second powder layer at a predetermined time, and estimating the powder layer thickness of the second powder layer based on the measured temperature of the second powder layer and the reference temperature calculated by means of the mathematical function for the predetermined time point.

A method of performing visualized measurement on thickness distribution of a paint film and an apparatus therefor. A measurement target region is heated by a heating unit that applies a light beam while moving relative to the measurement target region of a measurement target structure. A sensing unit moving together with the heating unit generates a plurality of thermal images related to a phenomenon in which thermal energy is propagated in the measurement target region by scanning and photographing the heated measurement target region. The thermal images in a dynamic state are converted into time-spatial-integrated thermal images in a static state by performing coordinate transformation according to a time-spatial-integrated coordinate transformation algorithm. A thickness of the paint film is calculated by using a Fourier thermal conduction equation. A noise caused by an external heat source is removed by subtracting a pre-heating time-spatial-integrated thermal image from the converted time-spatial-integrated thermal image.

The present disclosure discloses a water heater, and a scale detection system and method. The scale detection system comprises: a first temperature detector configured to acquire a first temperature of a heat exchange zone of a water heating device; a second temperature detector configured to acquire a second temperature indicating a water temperature in the water heating device; and a controller in communication with the first temperature detector and the second temperature detector, and configured to acquire a temperature difference between the first temperature and the second temperature based on the first temperature acquired by the first temperature detector and the second temperature acquired by the second temperature detector, and determine that a scale generation amount in the water heating device reaches a preset threshold when at least one of the following judgment conditions is met: the first temperature is not less than a preset temperature threshold; and the temperature difference is not less than a preset temperature difference threshold. The present disclosure can ensure that a user can be reliably and timely reminded to clean the scale under different working conditions.

A portable optic metrology thermal chamber module including a housing defining a thermal chamber, with a thermally isolated environment arranged for holding an optic device under test, the housing having an optic stimulus entry aperture configured for entry of a stimulus beam, from a metrology system stimulus source through the entry aperture onto an entry pupil of the device to an image analyzer, and a module mount coupling to modularly mount the portable optic metrology thermal chamber module to a support of a metrology system of the metrology system stimulus source so as to removably couple the portable optic metrology thermal chamber module as a unit to the support in a predetermined position relative to the metrology system stimulus source, and the housing is sized and shaped so that the portable optic metrology thermal chamber module is portable as a unit for moving to and removing from the predetermined position.

A method for monitoring the wear of a refractory lining of a blast furnace using modelling of a part of the blast furnace and thermal field calculation. Computer program allowing to perform such a method.