We propose a method that realizes laser ranging and communication at the same time based on dual-pulse interval modulation (DPIM). The transmission of binary data bits in the communication process is realized by sending two laser pulses continuously, and the time interval between the dual pulse is used to characterize the value of this bit (0 or 1). Meanwhile, the echo signal received by the communication transmitter is also a dual pulse signal, which enables laser ranging by the time-of-flight (TOF) principle. This method can effectively improve the reliability of system communication. Furthermore, the system structure is rather simple, including one piece of field programable logic gate array (FPGA) chip, one piece of time-to-digital converter (TDC) chip, and a transmitting and receiving circuits. The experimental results show that this method and system can achieve effective and reliable transmission of 2-D images and characters at the ranging accuracy of a single laser ranging system.

The aim of the present study was to develop a water-soluble biomarker for the detection of breast cancer using quantum dots (QDs) conjugated to Ki‑67, a nuclear protein associated with the cell cycle. Ki‑67 is also a marker of cell proliferation, with expression levels categorizing good and poor prognosis in invasive breast cancer. Ki‑67 is a clinically used biomarker for breast cancer diagnosis, treatment and prognosis. Owing to the optical and chemical advantages of QDs, QD‑based nanotechnology may aid the construction of a biomedical imaging platform for the study of cancer cell behavior. In the present study, a biomarker was prepared by employing the water‑soluble CuInS2/ZnS QDs conjugated to an anti‑Ki‑67 monoclonal antibody to detect Ki‑67 expression in breast cancer. The QDs, which were hydrophobic and coated with octadecylamine, were encapsulated with an amphiphilic biocompatible centipede‑like polymer, and then conjugated to anti‑Ki‑67 monoclonal antibodies (QD‑Ki‑67 probes). The QD‑Ki‑67 probes retained the original optical properties of the unadorned QDs and did not exhibit distinct toxic side effects in in vitro cytotoxicity experiments. Therefore, this CuInS2/ZnS QD‑labeled bioprobe, with a high quantum yield and low cytotoxicity, is a promising candidate for bioimaging and may be used as a cell label.

We have proposed a time-domain extremum phase shift laser ranging method based on ergodic under-sampling to address the issues of high sampling rate and complex hardware implementation in conventional phase shift laser ranging systems. This method is combined with the spline interpolation algorithm to further enhance the range resolution and precision. Compared with traditional frequency domain phase shift laser ranging methods, our method has the advantages of a simpler calculation process, higher measurement precision, a lower sampling rate, and easier hardware implementation. We have set up a phase shift laser ranging system with an FPGA to test the viability of the proposed method. The proposed method has shown superior ranging performance than the conventional DFT frequency domain method. In addition, the use of the spline interpolation algorithm can further enhance the resolution and precision. We hope that this ranging method can provide a reference for reducing the hardware complexity of phase shift LiDAR and enhancing ranging precision.

We propose a pulsed laser ranging method based on a multiecho delay trigger, which improves the precision of pulsed laser ranging. A signal delay unit is used to accurately delay the pulse-echo signal. In a fixed time window, the echo delay pulse triggers the laser transmitter to generate pulsed laser light; meanwhile, the counter records several echo pulses received, and then, the actual distance can be calculated. In terms of improving the ranging precision, this method overcomes the essential of higher time resolution time-to-digital converter (TDC) chip in traditional time-of-flight (TOF) pulsed laser ranging. The method can be realized by using a field-programmable logic gate array (FPGA) chip, a delay unit, and a set of laser transmitters and receivers, which makes the system structure simple and low cost. Experimental results show that this method can achieve more accurate distance measurement and significantly reduced error, to the best of our knowledge, which improves the pulsed laser ranging from centimeter- to millimeter-order precisions. We believe that this method has a promising application prospect in the field of high-precision pulsed laser ranging of fixed targets.