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Personalised drug delivery systems with the ability to offer real-time imaging and control release are an advancement in diagnostic and therapeutic applications. This allows for a tailored drug dosage specific to the patient with a release profile that offers the optimum therapeutic effect. Coupling this application with medical imaging capabilities, real-time contrast can be viewed to display the interaction with the host. Current approaches towards such novelty produce a drug burst release profile and contrasting agents associated with side effects as a result of poor encapsulation of these components. In this study, a 3D-printed drug delivery matrix with real-time imaging is engineered. Polycaprolactone (PCL) forms the bulk structure and encapsulates tetracycline hydrochloride (TH), an antibiotic drug and Iron Oxide Nanoparticles (IONP, Fe3O4), a superparamagnetic contrasting agent. Hot melt extrusion (HME) coupled with fused deposition modelling (FDM) is utilised to promote the encapsulation of TH and IONP. The effect of additives on the formation of micropores (10–20 µm) on the 3D-printed surface was investigated. The high-resolution process demonstrated successful encapsulation of both bioactive and nano components to present promising applications in drug delivery systems, medical imaging and targeted therapy.

A coherently injection-locked and beyond-bandwidth-modulated weak-resonant-cavity laser diode (WRC-FPLD) transmitter packaged by a conventional TO-56 can package for an upstream 10-Gb/s OOK transmission is demonstrated in a DWDM-PON. With specific temperature controlling, the WRC-FPLD is able to maintain its temperature during the process of injection locking. Based on the theoretical analysis of modified rate equations, the injection-locked WRC-FPLD exhibits not only a broadband gain spectrum but also a large modulation bandwidth. Successfully implementing injection locking enhances the high-frequency throughput response but inevitably impairs the throughput intensity at a low-frequency region. By properly increasing the injection-locking power, the modulation bandwidth of the injection-locked WRC-FPLD can be further improved. In addition, the extinction ratio and the signal-to-noise ratio (SNR) of the transmitted 10-Gb/s NRZ-OOK data can also be improved from 5.58 to 6.95 dB and from 5.43 to 6.18, respectively, by increasing the injection-locking power from -12 to -3 dBm, which improves the receiving power sensitivity by 1.6 dB. The optimized receiving power sensitivity at a requested bit error rate (BER) of 10-9 is -15.4 dBm by setting the injection-locking power at -3 dBm. After a 25-km transmission, such an overbandwidth-modulated and injection-locked WRC-FPLD reveals a receiving power sensitivity of -11.6 dBm at the same BER of 10-9.

The inherent data-erasing functionality of a 10-Gb/s colorless Fabry-Pérot laser diode (FPLD) wavelength controlled by reusing a downstream optical carrier with encoded data is explored. By operating the injection-locked colorless FPLD at high dc bias, the unique in situ data-erasing mechanism is attributed to the almost identical power-to-current slope, regardless of optical injection-locking level. When reusing the downstream carrier, the injection-locked upstream colorless FPLD can significantly suppress the extinction ratio of the residual 10-Gb/s downstream data from 7.1 to th indicates a BER of -10. This releases the typical demand on high power budget requested for downstream data transmission and carrier reusing. The large parametric tolerances of such a data-erasable and carrier-reusable colorless FPLD transmitter also facilitate its practical application in dense-wavelength-division multiplexed passive optical networks.

Light-induced photoluminescence (PL) switching using azobenzene-doped liquid crystal (LC)-dispersed quantum dots (QDs) is demonstrated in a format of LC cell and LC-infiltrated tube. Before light irradiation, excitation photons undergo multiple scattering events before emission out of the LC cell, and PL intensity is high. Upon the light irradiation, the trans-to-cis photoisomerization of azobenzene makes the QD-dispersed LCs highly transparent, thus allowing most excitation photons to pass through LCs and decrease PL intensity. This demonstration may allow a new modulating technique for future development of light-switchable, QD-emission-based display or photonic devices.

This paper presents large-angle color dispersion using a holographically fabricated 2-D subwavelength transmission grating. A dispersion angle of 68° is observed within continuous spectrum dispersion from 360 to 700 nm at an incident angle of 20 ° using white light as a probe beam. By changing the angle between the sample normal and the probe beam, the dispersed spectrum can be tuned at a spectral resolution of 3.6 nm per degree.