Reflective type high-speed camera shooting schlieren system applied to constant volume combustion bomb and capable of correcting chromatic aberration

[0020] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0021] The reflective constant volume incendiary high-speed imaging schlieren system shown in the figure that can correct chromatic aberration includes a light source 1, an optical fiber 2, a condenser lens group 3, a slit device 4, a first mirror 5, and a collimator arranged in sequence along the optical path. Mirror 6, constant volume incendiary bomb 7, schlieren mirror 8, second reflector 9, knife edge 10 and high-speed camera 11; light source 1 is an LED-light source, the light input end of fiber 2 is connected to light source 1, and the light output of fiber 2 The end is connected to the condenser lens group 3. The focal point of the condenser lens group 3 and the focal point of the collimator lens 6 after being reflected by the first mirror 5 coincide at the slit device 4, so that the size of the light source can be adjusted by adjusting the aperture of the slit device 4 , It can also be more convenient and more accurate to determine the focus of the condenser lens group when debugging the schlieren system. The knife edge 10 is located at the focal point of the schlieren mirror 8 after being reflected by the second reflector 9. This can be adjusted by adjusting the aperture of the knife edge 10. The size of the image finally projected into the high-speed camera 11 is determined.

[0022] In the above technical solution, the condenser lens group 3 is composed of a first convex lens 12.1, a first concave lens 13.1, and a second convex lens 12.2 arranged in sequence along the optical path. The distance between the first convex lens 12.1, the first concave lens 13.1, and the second convex lens 12.2 Adjustable, so by adjusting the distance of the first convex lens 12.1, the first concave lens 13.1, and the second convex lens 12.2 to correct the chromatic aberration caused by the light emitted by different light sources.

[0023] In the above technical solution, the condenser lens group 3 is installed in the condenser lens barrel 14. The condenser lens barrel 14 includes a first convex lens barrel 14.1, a first concave lens barrel 14.2 and a second convex lens barrel 14.3; a first convex lens barrel 14.1 One end of the inner ring is provided with a first annular groove 15.1 for fitting the first convex lens 12.1, the first concave lens barrel 14.2 is provided with an inner cavity 16 for fixing the first concave lens 13.1 along the axial direction, and the second convex lens barrel 14.3 One end of the inner ring is provided with a second annular groove 15.2 for inserting the second convex lens 12.2; one end of the first concave lens barrel 14.2 is connected with the end of the first convex lens barrel 14.1 having the first annular groove 15.1 through a thread, the first The other end of the concave lens barrel 14.2 and the end of the second convex lens barrel 14.3 having the second annular groove 15.2 are connected by threads. Install each lens in its corresponding lens barrel. Each lens barrel is connected by threads, and the degree of screwing between the lens barrels is used to correct the chromatic aberration in different situations, so as to avoid direct contact with the mirror surface and dirty mirror surface during lens adjustment. , While adjusting the distance between the mirrors can also be more stable. What is important is that in the condenser lens group, when the convex lens barrel is completely screwed into the concave lens barrel, the distance between the convex lens and the concave lens is equal to 0 at this time.

[0024] In the above technical solution, the first annular groove 15.1, the second annular groove 15.2 and the inner cavity 16 are all provided with an annular stop ring 17, and the annular stop ring 17 is fixed to prevent the lens from being scratched or crushed. , And easy to clean and replace the lens.

[0025] In the above technical solution, the slit device 4 is an annular slit device with adjustable aperture. When the focal point of the condenser lens group 3 is determined, the aperture of the slit device 4 is adjusted to 0, and when projected onto the slit device 4, a bright The position of the slit device 4 is the focal plane of the condenser lens group 3.

[0026] The working process of the present invention: firstly, the light emitted by the light source 1 is transmitted to the condenser lens group 3 through the optical fiber 2, and the distance between the lenses of the condenser lens group 3 is adjusted so that it is finally projected on the slit device 4 and there is no color in the outermost circle of the light. The aperture of the slit device 4 is adjusted to 0, and the distance between the slit device 4 and the condenser lens group 3 is adjusted so that the slit device 4 is a bright spot. At this time, the surface of the slit device 4 is The focal plane of the condenser lens group 3, the slit device 4 is a point light source; then, the point light source is emitted from the focal point of the condenser lens group 3, reflected by the first mirror 5, and then projected to the collimating lens 6, after collimation The light reflected by the mirror 6 forms a uniformly mixed color parallel light and is projected into the constant volume combustion bomb 7; then, the measured area in the constant volume combustion bomb 7 burns to form a spherical flame, the fluid is disturbed, the refractive index changes, and the parallel light passes through the The measurement area reaches the schlieren mirror 8, the light reflected by the schlieren mirror 8 passes through the knife edge 10 after being reflected by the second mirror 9, and finally forms an image on the high-speed camera 11.

[0027] The above are only specific embodiments of the present invention. It should be pointed out that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. within.