The tomography schlieren method is useful for calculating the non-axisymmetric temperature field, which is relevant to many industrial applications. However, the traditional tomography schlieren method requires bulky imaging devices, which limits its application. Thus, this paper proposes a non-contact three-dimensional temperature field measurement method based on the rotating tomography schlieren method. Projections from different directions of the temperature field are obtained at different angles using a transmission schlieren system, which is controlled by a designed rotating tomographic mechanism. The calibration schlieren method and the projection reconstruction algorithm are used to calculate the 3D temperature field. Verification experiments of single flame and double flame showed that the relative error of the reconstructed temperature was approximately 3.7% compared with a precision thermocouple.

The typical non-axisymmetric temperature field distribution in the tail nozzle outlet area of the combustion chamber of an aircraft engine can reflect the operating state of the engine. As an effective non-axisymmetric temperature field non-contact measurement method, the traditional background oriented schlieren method has the problem that the extraction accuracy of light deflection is not high. In this paper, interference fringes are introduced into the schlieren measurement, and the highly sensitive fringe offset replaces the traditional background speckle offset for measurement, which realizes the accurate reconstruction of the non-axisymmetric temperature field. Firstly, through the Interferometric stripe schlieren composed of multiple sets of double-slit interferometric systems and imaging sensors, the offset of the interference fringe after passing through the non-axisymmetric temperature field is measured by image processing, and the spatial refractive index field is reconstructed by the

The light pen is one of the most useful spatial coordinate measurement methods. However, due to the principle of vision measurement, the traditional light pen has the disadvantages such as limited measurement range, large structure size and complex calibration process. In order to revolutionize the design of light pen, this paper proposes a full space coordinate measurement method with a portable light pen by using hybrid light field imaging. Firstly, a light field imaging system with depth estimation ability has been introduced to simplify the light pen structure to three target points by using P3P method. In order to improve the accuracy of the depth estimation, a hybrid imaging method and EPI method have been used. Secondly, a full spatial measurement method with a rotation platform has been presented in detail. Finally, the experiments have been designed to verify the effectiveness and accuracy of the proposed method.

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