Reading a printed page, adding notes beside a laptop and returning to a book later can involve small changes to a desk's lighting. The brightness control is the part of the lamp that turns those preferences into a physical action.
Two familiar approaches are a set of brightness steps and a continuous adjustment range. Zhexian's ZX-TC1 and ZX-TS1 illustrate the difference through their documented controls: a head-mounted panel with five brightness levels, and a slide dimmer with a 10–100% range.
Five defined levels on ZX-TC1
The ZX-TC1 desk lamp offers five brightness steps from the control panel on its head. This gives the user a set of defined levels to choose between when adjusting the light.
Its Reading and Comfort modes both provide five-step brightness adjustment. The named white-light settings are 4000 K and 2700 K respectively; those colour settings are separate from the number of brightness levels.
For a reader returning to the same desk activity, a small set of levels offers a straightforward choice between available settings. The original ZX-TC1 specifications document the five steps without assigning a percentage to each one. They should therefore not be relabelled as 20%, 40%, 60%, 80% and 100%.
Continuous adjustment on ZX-TS1
The ZX-TS1 desk lamp uses a slide dimmer for continuous brightness adjustment from 10% to 100%. The user can vary the setting across that documented range rather than choose among five defined levels.
The slide control concerns brightness. A separate rotary selector chooses colour temperature in steps. Continuous dimming therefore does not mean continuous adjustment of every lighting characteristic.
The distinction is useful at a desk where the desired light level may sit between a small number of presets. The slide gives the user an adjustment within the available range. Its stated lower end is 10%; switching the lamp off is a separate operating state.
A range does not describe the whole response
A dimming range and the movement of a control describe different things. In its discussion of dimming curves, Lutron explains the relationship between control input and light output, including linear and non-linear responses.
That general distinction matters when reading a lamp's specification. A slider halfway along its travel does not, by itself, establish half the measured light output. Likewise, five brightness levels do not establish five equal changes in output.
The Zhexian documents identify the control formats but do not provide complete control-position curves for these models. The 10–100% description should not be converted into a matching percentage of electrical power consumption.
Brightness and white appearance remain different choices
The U.S. Department of Energy's explanation of tunable lighting describes interfaces that control intensity and white-light colour separately. ZX-TC1's panel and ZX-TS1's slide-and-rotary arrangement make those two choices available through their respective interfaces.
Their everyday appeal lies in how the adjustment is presented: five defined brightness steps on TC1, or a continuous slide adjustment on TS1. Neither format alone determines which setting suits every page, user or surrounding room.
To discuss these control options for a desk-lamp range or study-space application, contact Zhexian about ZX-TC1 and ZX-TS1.