Recent years has seen a kind of an epidemic in short-sightedness in almost all countries, part of the reason can be attributed to an increase in artificial light from televisions, computers and mobile phones. It is a sad fact that our eye health is deteriorating so rapidly that it is becoming increasingly important to act now while we can. And we have to choose the right type and extra features to ensure the lamp protects our eyes and fits our needs. Yet buying a new eye protection lamp may sound simple, but the sheer number of options can make it a little trickier than you'd expect. Use this helpful desk lamp guide to make an informed decision.
Blue light is Everywhere
Sunlight is the main source of blue light, and being outdoors during daylight is where most of us get most of our exposure to it. In the meantime, there are also many man-made, indoor sources of blue light, including fluorescent and LED lighting and flat-screen televisions.
Most notably, the display screens of computers, electronic notebooks, smartphones and other digital devices emit significant amounts of blue light. The amount of HEV light these devices emit is only a fraction of that emitted by the sun. But the amount of time people spend using these devices and the proximity of these screens to the user's face have many eye doctors and other health care professionals concerned about possible long-term effects of blue light on eye health.
Note: As of September 1, 2009, IEC/EN 62471, Photobiological Safety of Lamps and Lamp Systems, was fully applied to all LED lighting products. It gives guidance for evaluating the photobiological safety of lamps and lamp systems including luminaries. Specifically, it defines exposure limits, references measurement techniques and the classification scheme for the evaluation and control of photobiological hazards from all electrically powered incoherent broadband sources of optical radiation in the wavelength range from 200 nm through 3000 nm.
Illuminance is a term that describes “the measurement of the amount of light falling onto and spreading over a given surface area". Illuminance also correlates with how humans perceive the brightness of an illuminated area. The SI unit for illuminance is lux (lx).
Today, the light level is more common in the range 500-1000 lux - depending on activity. For precision and detailed works, the light level may even approach 1500 - 2000 lux. Light power should also be in coordination with the surrounding environment of the light and dark situation, the brightness of the light and the environment should not be too large in the environment of low brightness occasions.
Stroboscopic refers to the depth of the luminous flux of electric light source fluctuation. The greater the depth of the luminous flux fluctuation, the more serious the stroboscope. Recent investigations show that LED lighting products with good quality ballasts may exhibit anomaly high flicker rates, especially under dimming conditions.
Color temperature is a measurement that indicates the extent of yellowish or bluish tint to a white light. High color temperatures are bluish while low color temperatures are yellowish.
A desk lamp's color temperature is measured in Kelvin (K) and typically falls between 2,700K and 7,500K. The higher the Degrees Kelvin, the whiter the color temperature. Task lighting is usually more effective if it falls on the cooler end of the color temperature spectrum. A measurement of 3,500-5,500K is ideal.
Color Rendering Index
Color Rendering Index (CRI) is the measurement of how colors look under a light source when compared with sunlight. The index is measured from 0-100, with a perfect 100 indicating that colors under the light source appear the same as they would under natural sunlight. Generally speaking, lights with a CRI that is measured greater than 80 are considered to be more than acceptable for most applications (CRI that is measured greater than 90 is generally considered "High CRI" lights).
The best lamp in the world is no good if it's in the wrong place. Similarly, if you want to change position, it's much easier to be able to bring the light towards you than to have to move your work and materials towards the light. Your lamp should generally be positioned so it casts light onto the page from your non-dominant side. Lamps that have an adjustable or flexible arm can come in very handy. They allow you to direct light to the area you need it most. Likewise, a desk lamp with a hinged arm usually allows you to position the lamp in two or more positions.
What Makes a Lamp Great for Eyes?
You need to understand what makes your eye strain easily. When a lamp offers uneven light, or provides with light that is too bright or too low for what you're doing, it causes your eye to strain and you need to change a new one.