Abstract: Provided are an optical system and a mixed reality device. The optical system includes a projection apparatus, a substrate layer and a diffraction grating layer. The projection apparatus is configured to project two beams of image light. The substrate layer has two side surfaces and two planes, where each of the two side surfaces is configured to receive a respective one of the two beams of the image light, and the two planes are configured to totally reflect each of the two beams of the image light entering the substrate layer. The diffraction grating layer is disposed on at least one plane of the substrate layer and is configured to diffract, in a reflective manner or a transmissive manner, the two beams of the image light propagating in the substrate layer, where energy of target image light diffracted out of the diffraction grating layer is uniformly distributed.

Abstract: Provided are an optical system and an aiming device. The optical system includes a wavefront modulation element with a first surface and a second surface disposed opposite to each other. The first surface of the wavefront modulation element is configured to receive a first light wave without a complete plane wavefront. The second surface of the wavefront modulation element is configured to emit a second light wave with a complete plane wavefront obtained due to the light beam shaping of the first light wave by the wavefront modulation element. The aiming device includes a housing and the optical system.

Abstract: Provided are an optical system and a mixed reality device. The optical system includes a projection apparatus, a substrate layer and a diffraction grating layer. The projection apparatus is configured to project two beams of image light. The substrate layer has two side surfaces and two planes, where each of the two side surfaces is configured to receive a respective one of the two beams of the image light, and the two planes are configured to totally reflect each of the two beams of the image light entering the substrate layer. The diffraction grating layer is disposed on at least one plane of the substrate layer and is configured to diffract, in a reflective manner or a transmissive manner, the two beams of the image light propagating in the substrate layer, where energy of target image light diffracted out of the diffraction grating layer is uniformly distributed.

Abstract: A cationic copolymer represented by the following formula (I) has a viscosity average molecular weight in a range from 2 million to 10 million. In the cationic copolymer, the mole fractions of three structural units corresponding to three monomers are as follows: x being in a range from 0.01 to 20%, y being in a range from 0 to 15%, and z=1?x?y. When used in the construction of leaking stoppage in an oil well, a cationic chemical lost circulation additive prepared with the cationic copolymer is mixed with an anionic drilling fluid in a section of the wellbore where lost circulation occurs. Then neutral reaction and cross linking reaction occur, so that the viscosity of the resulting mixture rapidly increases to form a space grid structure. This blocks off the leakage path, and thus effects on efficient leaking stoppage in a short time period.

Abstract: A crank circular slider mechanism that includes a multi-row reciprocating motion part and a one-row reciprocating part. The multi-row reciprocating motion part has a guiding part divided by a longitudinal groove into two rows parallel to each other, each of which has a hole for a circular slider. The one-row reciprocating motion part has a guiding part which can be inserted into the longitudinal groove of the multi-row reciprocating motion part along the thickness direction, so as to vertically traverse the multi-row reciprocating motion part. The guiding part of the one-row reciprocating motion part includes a hole receiving a middle circular slider. Two circular sliders are mounted in the same phase; the middle circular slider is sandwiched therebetween and is located with a 180 degree phase difference compared to them. Adjacent circular sliders are secured to each other.

Abstract: A cationic copolymer represented by the following formula (I) has a viscosity average molecular weight in a range from 2 million to 10 million. In the cationic copolymer, the mole fractions of three structural units corresponding to three monomers are as follows: x being in a range from 0.01 to 20%, y being in a range from 0 to 15%, and z=1?x?y. When used in the construction of leaking stoppage in an oil well, a cationic chemical lost circulation additive prepared with the cationic copolymer is mixed with an anionic drilling fluid in a section of the wellbore where lost circulation occurs. Then neutral reaction and cross linking reaction occur, so that the viscosity of the resulting mixture rapidly increases to form a space grid structure. This blocks off the leakage path, and thus effects on efficient leaking stoppage in a short time period.

Abstract: The invention provides a crank circular slider mechanism comprising multi-row reciprocating motion part and one-row reciprocating part: the multi-row reciprocating motion part has a guiding part which is divided by a longitudinal groove into two rows parallel to each other, respectively named by the first row of guiding section on which is provided a first hole receiving the circular slider; and the second row of guiding section on which is provided a second hole receiving the second circular slider, the one-row reciprocating motion part has a guiding part which can be inserted into the longitudinal groove of the multi-row reciprocating motion part along the thickness direction, so as to transverse vertically the multi-row reciprocating motion part, the guiding part is provided thereon with a hole receiving the middle circular slider, the first circular slider and the second circular slider are mounted in the same phase, the middle circular slider is sandwiched between the first circular slider and the second