Abstract: A fluid rotary joint assembly capable of high rotational speed exceeding a maximum rotational speed of a single rotary joint is disclosed herein. For example, the fluid rotary joint may be capable of exceeding rotational speeds greater than 1500 RPM. The fluid rotary joint assembly may have several single-stage fluid rotary joints and multiple gear devices wherein a relative speed between the first and second rotary parts of each single stage fluid rotary joint does not exceed a maximum rotary speed (e.g., 500 rpm). The fluid rotary joint assembly incorporates speed reduction within each stage through the gear device. By controlling the relative speed between the first and second parts of each of the fluid rotary joints to be less than or equal to a maximum allowable rotational speed (e.g., less than or equal to 500 RPM), the fluid rotary joint assembly provides for reliable operation at high rotational speeds between the first stage and the last stage.

Abstract: The present invention relates to a method for restriction endonuclease-mediated primer generation-rolling circle amplification (PG-RCA), including the following steps of: 1) thiol-modifying a single-stranded DNA (ssDNA) at a restriction site of a restriction endonuclease; 2) cyclizing the thiol-modified ssDNA to obtain a thiol-modified circular ssDNA; and 3) using the thiol-modified circular ssDNA obtained in step 2) as a template, adding the template into a reaction system of a target DNA primer to be detected, a DNA polymerase with strand displacement, and a restriction endonuclease for multiple cycles of rolling circle amplification, to amplify a molecular signal of target DNA.

Abstract: A two-channel fiber optical rotary joint has been invented in which optical signals can be transmitted simultaneously along two optical passes through a single mechanical rotational interface for both single mode fiber and multi mode fiber. The first channel of light path consists of a pair of micro-collimators, or a pair of fibers, co-axially fixed in 2 holders respectively. The light signal from one of micro-collimator, or fiber can be directly coupled into another micro-collimator, or fiber. The second channel of light path is off-axis arranged, including a pair of conventional collimators, a pair of first reflecting surfaces and a pair of second reflecting surfaces. The light signal emitted from one of the said conventional collimator will be reflected by one of the said first reflecting surface, one of the said second reflecting surface, another said second reflecting surface, and another said first reflecting surface, then coupled into another said conventional collimator.

Abstract: The present invention relates to a device for use in a fiber optic system that may be a communication system, a sensing system or other system using guided-wave optical components. Reducing the number of lenses required to couple the waveguides and the free-space paths in the device offers the dual advantages of a reduced component count and simplified alignment. In an exemplary device having a first and second waveguides, a birefringent optical system defines bidirectional, polarization-dependent free-space paths. One of the bidirectional, polarization-dependent, free-space paths couples at least the first waveguide to the second waveguide. The birefringent optical system includes at least one prism for bending one of the polarization-dependent paths in a clockwise direction and one of the polarization-dependent paths in a counterclockwise direction.

Abstract: An anti-backlash planetary gear system is disclosed for a multi-channel fiber optic rotary joint which requires 2:1 gear ratio. By adding a local degree of freedom, the planet gear assembly could be tilted relative to the carrier by a spring-loaded annular ring through a spherical feature thus force the three, or more planet gears symmetrically mesh into the sun gear and internal gear. A couple of elastomeric sleeves are introduced into the connection between planet housing and carrier so as to balance the load evenly among the three planet assemblies and to reduce the speed fluctuation of transmitted motion as well as the noise and vibration.