IEC 61947-2:2001 pdf download

IEC 61947-2:2001 pdf download.Electronic projection – Measurement and documentation of key performance criteria – Part 2: Variable resolution projectors.
3.37
transmission
measure of the amount of light that is transmitted by an optical medium relative to the total amount of incident light
3.38
vertical lines
number of active lines in a picture
3.39
viewing anglehalf gain
angle between the direction of maximal reflection and the direction where the luminance drops to 50 % of its value
NOTE This quanlity shoufd be measured In the centre of me viewing screen
3.40
visible lIght
electromagnetic radiation to which the human observer is sensitive through the visual sensations that arise from the stimulation of the retina of the eye
NOTE The spectral range is typically considered to have s range 01 380 nm to 780 nm (3 800 A to 7800 Al.
3.41
zoom lens
focusing lens that has a second, primary adjustment for focal length
NOTE This capabibly allows smaller or larger Image sizes from a tited projection drstance. The zoom ratio is typically stated in a range of screen wichh.proeclici, distance ratios. for ezampte, a 1:2 to 1:4 zoom lens could locus s 10 m or a 5 m wide image horn a 20 m throw distance.
4 General requirements
This part of IEC 61947 Is intended to specify a complete description of the product. In accordance with these intentions, a complete specification (see example in annex D) shall be used in product descriptions, If a particular specified measurement was not performed, the complete specification shall include the text “not measured” or “data not available” under that measurement section.
NOTE The use of partial specifications in product descriptions is not recommended since many of the specified measurements are interrelated (for example, resolution and light outpulj.
All measurements and specitications shall conform to the following.
— The measurements of light output, visual resolution, and blanking found In this standard are interrelated and shall be measured and specified as a set.
– The parameters and measurement criteria specified in this document allow for a wide variety of equipment performance. Secondary, non-conforming specifications are permitted to allow flexibility for special features of various products and technologies, but shall be displayed in the same type face font and density at least 25 % smaller in size.
– A sample from normal production runs shall be used to establish the specifications. Results from measurements ot preproduction and prototype units shall be identified as preliminary specifications.
– The sample units shall not be adjusted or enhanced beyond normal production parameters, especially in a way that would reduce the normal operating life of any component or of the entire display.
All optical, electrical focus, and convergence controls shall be adjusted for the sharpest display over the largest possible percentage of the illuminated area, using appropriate patterns from an internal or external test generator as needed.
— The equipment shall be allowed to stabilize without further adjustment for a minimum of
15 mm, at a nominal ambient room temperature of (23 ± 5) C, before taking
measurements.
NOTE Meaauren,ent Could also be lairen alter 1 h 01 operation with all covers in p(ace. wtr,le raster. as Intended br normaJ use
– Measurements shall take place in a Iightproof room where the only source of illumination is the projector. Less than 1 % of the light on the screen shall be from any source other than the projector. The projector should be operated with all covers in place as in normal operation.
— The display device shall be adjusted br a 4:3 (horizontal:vertical) aspect ratio, If It Is capable of It. The horizontal and vertical size of the scanned area shall be adjusted to the maximum usable diagonal size of the light modulator or source, such as a light valve or CRT, with the specified aspect ratio.
– Displays designed for only one aspect ratio shall be adjusted to. and measured at. the design aspect ratio that shall be specified with the light output.
— Devices that use a separate screen shall be positioned relative to the screen in accordance with the angle, height, and distance specified in the manufacturer’s set-up instructions,
– Displays with integral screens shall be adjusted so as to fill exactly their viewing screens, The displays shall not delete nor hide any data in the corners or edges in the horizontal dimension. The vertical dimension shall then be adjusted to achieve a 4H:3V aspect ratio, if applicable.
— All measurements shall be taken with no adjustments made between measuremonts
– Measurements shall be specified in international units, or both international and national units, with international units listed first.
5 Light output measurement and specification
The light output specification shall be stated in lumens t or projectors with separate screens, and in candela per square metre (nits) for displays with self-contained screens.