Quick answer
Define which distance is being measured, test the exact fitting from the page and both pillows, then dimension the accepted setting.
The distance between a bedside reading light and the bed should be set by the page, guest eye line and reach, not by a universal number. Start with the finished mattress, pillow and expected reading posture. Place the actual fitting temporarily, aim it at a book, then check the result from the reader and the other pillow. Measure and record the accepted horizontal and vertical distances from permanent room datums after this test. A number copied from another headboard can put the source in view or leave the page in shadow.
Define which distance matters
“Distance from bed” can mean offset from the mattress edge, distance from the headboard face, reach from the pillow, or distance from the light source to the book. These are not interchangeable. On the drawing, name the datum for every measurement. Include the finished wall surface and upholstered thickness, because a light mounted behind or proud of a headboard changes the effective geometry.
Mark the likely book position for upright and reclined reading. If guests may use both postures, test both. The mounting-height guide deals with the vertical decision; this page focuses on how the fitting relates to the bed in plan and section.
Test page light and eye-line exposure together
Move the sample until the page is useful without the guest looking straight into the source. Then sit on the other side of the bed and look toward the fixture. If the source or spill is uncomfortable, consider a different offset, shielding or optic. Do not assume moving it farther away always helps: the page result and aiming range may worsen.
The documented MD-WL-Y135 has an adjustable head, but its product pack does not provide a universal bedside mounting distance or confirmed cut-out. Request the exact photometric and installation data for the ordered configuration. A 30° beam value in the pack describes one optic, not the final light pattern at every bed distance.
Check reach and nearby obstructions
Can the guest reach the switch or move the head from a natural resting position? Does the pillow cover the fitting? Does a side table, wall shelf or deep headboard block the beam? Test the room with the intended soft furnishings, not an empty construction shell. For a swing arm, inspect its whole travel and parked position; a nominal arm length is not the same as a comfortable usable reach.
Keep the control and charging locations separate on the schedule. A port that appears close on a drawing may still be inaccessible behind a wide mattress or side table.
Record a repeatable setting
Once the room sample is accepted, dimension the source center, faceplate and control from fixed datums: finished floor, wall, headboard edge and bed centerline. Photograph the accepted aim and note the exact fixture variant. Give the contractor an approved elevation and section. On the first installed room, recheck the same tasks before repeating the placement across the floor.
For an asymmetric room, record left and right positions separately. A wardrobe, window or side table may force a different solution on one side. The acceptance test should demonstrate equivalent usability, even if the two measured offsets are not identical.
