What is blue light?
Blue light belongs to the shorter wavelengths of the visible spectrum. The sun is a natural source; screens and LED lighting also emit it, generally at much lower levels than daylight. Light also plays a part in the sleep–wake rhythm, with an effect that depends, among other things, on the time of exposure. Findings concerning filtering glasses are examined in the next section.
Screen discomfort is a different question. Prolonged close work, less frequent or incomplete blinking, reflections, lighting and an unsuitable prescription can contribute. This is the whole picture examined when discomfort appears after screen work.
Are blue-light glasses really necessary?
A blue-light filter reduces some of the blue light passing through the lens. It differs from anti-reflective coating, which reduces reflections on the lens surface.
Studies have not established that these glasses relieve screen-related eye strain. A Cochrane review concludes that they may make little or no short-term difference compared with lenses without this filter. Results concerning sleep remain uncertain.
If you enjoy wearing a pair with a blue-light filter, that preference can guide your choice. It does not replace an appropriate prescription, breaks or adjustments to your workspace.
Screen comfort: habits and vision checks
For long working or study days, start with the setup. Position the screen at a distance where you can read without moving your head forward; enlarge the text rather than constantly moving closer. Match its brightness to the room and move the lamp or screen if a reflection interferes with reading. With a laptop, a stand and separate keyboard can help you choose screen height and hand position independently.
Take regular breaks from close work and remember to blink fully. If dryness, blur or discomfort persists, have your eyes checked to look for the cause. A filter does not replace that check.
Choosing lenses for reading and screens
Lens type is chosen first according to the prescription and working distance. Single-vision lenses can be dedicated to reading or a screen; office lenses extend use towards intermediate distances. Progressives combine distance, intermediate and near vision, but their screen area may be narrower. Anti-reflective coating reduces reflections on the lenses; a blue-light filter remains a separate option. Describe your reading and screen distances so we can compare these choices.
Our optometrists supplement the instrument measurement with manual refraction: they ask you to compare prescriptions to determine which gives you the best vision. Eye examinations are free in Canggu, Ubud and Sanur. Our opticians then help you compare lenses according to your prescription and everyday life.
