To evaluate the optical performance of blue-light filtering spectacle lenses and investigate whether a reduction in blue light transmission affects visual performance and sleep quality. Experiment 1: The relative changes in phototoxicity, scotopic sensitivity, and melatonin suppression of five blue-light filtering plano spectacle lenses were calculated based on their spectral transmittances measured by a spectrophotometer. Experiment 2: A pseudo-randomized controlled study was conducted to evaluate the clinical performance of two blue-light filtering spectacle lenses (BF: blue-filtering anti-reflection coating; BT: brown-tinted) with a regular clear lens (AR) serving as a control. A total of eighty computer users were recruited from two age cohorts (young adults: 18–30 yrs, middle-aged adults: 40–55 yrs). Contrast sensitivity under standard and glare conditions, and colour discrimination were measured using standard clinical tests. After one month of lens wear, subjective ratings of lens performance were collected by questionnaire. All tested blue-light filtering spectacle lenses theoretically reduced the calculated phototoxicity by 10.6% to 23.6%. Although use of the blue-light filters also decreased scotopic sensitivity by 2.4% to 9.6%, and melatonin suppression by 5.8% to 15.0%, over 70% of the participants could not detect these optical changes. Our clinical tests revealed no significant decrease in contrast sensitivity either with (95% confidence intervals [CI]: AR–BT [–0.05, 0.05]; AR–BF [–0.05, 0.06]; BT–BF [–0.06, 0.06]) or without glare (95% CI: AR–BT [–0.01, 0.03]; AR–BF [–0.01, 0.03]; BT–BF [–0.02, 0.02]) and colour discrimination (95% CI: AR–BT [–9.07, 1.02]; AR–BF [–7.06, 4.46]; BT–BF [–3.12, 8.57]). Blue-light filtering spectacle lenses can partially filter high-energy short-wavelength light without substantially degrading visual performance and sleep quality. These lenses may serve as a supplementary option for protecting the retina from potential blue-light hazard. ClinicalTrials.gov NCT02821403

We study the recognition of surfaces made from different materials such as concrete, rug, marble or leather on the basis of their textural appearance. Such natural textures arise from spatial variation of two surface attributes: (1) reflectance and (2) surface normal. In this paper, we provide a unified model to address both these aspects of natural texture. The main idea is to construct a vocabulary of prototype tiny surface patches with associated local geometric and photometric properties. We call these 3D textons. Examples might be ridges, grooves, spots or stripes or combinations thereof Associated with each texton is an appearance vector, which characterizes the local irradiance distribution, represented as a set of linear Gaussian derivative filter outputs, under different lighting and viewing conditions. Given a large collection of images of different materials, a clustering approach is used to acquire a small (on the order of 100) 3D texton vocabulary. Given a few (1 to 4) images of any material, it can be characterized using these textons. We demonstrate the application of this representation for recognition of the material viewed under novel lighting and viewing conditions.

During the COVID-19 pandemic, the Hong Kong Government enforced a “school from home” policy between February and September 2020. This cross-sectional epidemiological study was conducted to investigate the prevalence of astigmatism and visual habits after the home confinement period. Vision screenings were conducted at three local government-funded primary schools in Hong Kong from October 2020 to December 2020. A total of 418 ethnically Chinese primary school children completed the eye examination and returned questionnaires concerning demographic information and visual habits. It was found that 46.5% (95% CI, 41.7–61.4%) of the children aged 8 to 11 years had astigmatism ≥ 0.75 D, which was predominately With-The-Rule astigmatism. The prevalence of astigmatism reported in these children is generally higher than that of studies conducted before COVID. Compared to their non-astigmatic peers, astigmatic children had a longer axial length (p < 0.001) and engaged in fewer outdoor activities (p = 0.04). Multiple linear regression analyses also revealed significant relationships between axial length and both cylindrical error and J0 astigmatism. Due to the high astigmatism prevalence, there is a pressing need for further studies on the long-term impact of the pandemic on children’s vision.

This study outlines the initiation of an interprofessional education (IPE) program designed for optometry and education students. The program aimed to foster interdisciplinary collaboration and improve the management of eye health in children with special educational needs (SEN) – a vulnerable and underserved group. This program incorporated lectures and workshops to impart essential knowledge about SEN and to develop the necessary attitudes and skills for conducting eye examinations. A key component involved vision screenings at two special education schools, where optometry (n = 43) and education students (n = 39) collaborated to serve 170 children with mild to moderate intellectual disabilities. Quantitative data was gathered pre- and post-program using a single-stage, five-level Likert scale. Qualitative insights were drawn from students’ reflective writings to evaluate their learning outcomes, understanding, and confidence in managing eye health for children with SEN. Of the participants, 37 optometry and 21 education students completed the survey (70.7% response rate). The survey results indicated significant improvements in understanding SEN characteristics (p ≤ 0.013) and increased confidence when conducting eye examinations for children with SEN (p < 0.007) after the training program. The analysis of reflective writings highlighted the program’s beneficial impacts on students. They recognized the value of interprofessional collaboration, reported enhanced professional competence, gained deeper insights into their own and their peers’ roles within multidisciplinary teams, and developed a strengthened sense of social responsibility. This IPE program proved to be an effective method for enhancing optometry and education students’ knowledge and confidence in managing eye health needs of children with SEN. The findings support the advocacy for continued collaborative efforts between healthcare providers and educators to ensure comprehensive care for this population. Such disciplinary collaboration provides positive evidence in early stages of training in both disciplines. Not applicable.