Full-color optical combiner with good imaging quality and a wide angle of incident light acceptance.

This work demonstrates a full-color optical image combiner for augmented reality head-up displays. In this device, the angle of the incident light of the computer-generated image reflected by it can vary over a large range. It achieves improved performance by using a combination of polarization interference filters (PIFs), quarter-wave retarders (QWRs), and polarization volume holograms (PVHs). The details for an example design and its performance are presented.

Intuitive understanding of the connection between Pancharatnam-Berry optical beam deflectors and polarization volume holograms.

An approximate beam propagation method is proposed as an intuitive simulation of the optics of Pancharatnam-Berry phase and polarization volume hologram devices. Using this method, the connection between and polarization properties of these two types of devices are made clear.

Pharmacological and non-pharmacological treatments for irritable bowel syndrome: Protocol for a systematic review and network meta-analysis.

BACKGROUND: The global prevalence of Irritable bowel syndrome (IBS) is estimated to be as high as 15% and a number of different non-pharmacological and pharmacological treatments have been used to manage IBS in clinical practice, which poses great challenges for clinicians to make appropriate decisions. Hence, a systematic review and network meta-analysis on all available pharmacological and non-pharmacological treatments for IBS is needed to provide reliable evidence. METHODS: We will search the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane IBD Group Specialized Trials Register, MEDLINE, EMBASE, and Chinese Biomedical medicine (CBM) from inception to 31, May 2019. Randomized controlled trials of pharmacological and nonpharmacological interventions for IBS will be included. Study quality will be assessed on the basis of the methodology and categories described in the Cochrane Collaboration Handbook. Primary outcomes are global or clinical improvement and quality of life. A Bayesian network meta-analysis would be performed, and relative ranking of agents would be assessed. A node splitting method will be used to examine the inconsistency between direct and indirect comparisons when a loop connecting 3 arms exists. RESULTS: Researchers will rank the effectiveness and safety of the potentials interventions for IBS according the characteristics of patients by conducting an advanced network meta-analysis based on Bayesian statistical model, and interpret the results by using GRADE approach. CONCLUSION: The conclusion of our study will provide updated evidence to rank the effectiveness and safety of pharmacological and non-pharmacological interventions for IBS. ETHICS AND DISSEMINATION: Ethical approval is not applicable since this study is a network meta-analysis based on published trials. PROTOCOL REGISTRATION NUMBER: CRD42018083844.