IEC 62906-5-3-2021 pdf free
IEC 62906-5-3-2021 pdf free.Laser display devices – Part 5-3: Measuring methods of image quality for laser projection display.
When different environmental conditions are used, they shall be noted in the measurement report.
4.3 Power supply
The power supply for driving the DUT shall be adjusted to the rated voltage ± 0,5 %, and the frequency shall be supplied at the rated frequency ± 0,2 %.
4.4 Warm-up time
The measurements should be carried out after the light output is sufficiently stable. It is defined as the time elapsed from when the supply source is switched on, and a full level of input signal is applied to the DIJT, until the repeated measurements with the interval of one minute show a variation within ten minutes in luminance (or illuminance) of less than 3 %.
4.5 Dark ambient conditions
The LPDs are intended to be measured under the dark room conditions. Any background illuminance at the image plane shall be less than 1 % of the projector maximum illuminance when measured with a projector mask blocking the direct beam from the projector (for example refer to [1J in 15.1.4). The measurements should be conducted in a room with matte black surfaces having a photometric reflectance of less than 3 %.
4.6 Measuring equipment
The configurations and operating conditions of the measuring equipment shall comply with the requirements specified in each item. Unless stated otherwise, the measurement point shall be at the centre of the image area to be measured. The measurement area at the image plane shall be at least 1 cm in diameter and contain at least 10 pixels x 10 pixels. It shall be confirmed that this number of pixels is sufficient by shifting the LMD 20 % laterally and verifying that the luminance is less than 2 %. A large enough measurement area is needed to average out speckle-Induced non-uniformity; in addition, the entrance pupil of the LMD shall be not less than 2 cm in diameter. To ensure accurate results for static measurements, the LMD integration time shall be a multiple n (n > = 1) of the frame time, or larger than 200 frame periods.
Filtered luminance meters and colorimeters are generally considered not to be accurate enough for laser projector measurements. Spectroradiometric instruments are preferred for these narrow bandwidth light sources. Filtered luminance meters and colorimeters shall only be used if they are corrected with a precision spectral radiance meter. However, it is noted that the correction factors shall be achieved for every given spectral distribution of the light from the screen (e.g. red, green, blue primaries, in addition to white and black).
To ensure repeatable measurements, the following requirements shall be applied.
1) Spot luminance meter: refer to ISO/CIE 19476. The spectral responsivity shall comply with
the CIE photopic luminous efficiency function, and the general i’(A) mismatch index f
should be no greater than 6 %; the relative luminance uncertainty shall not be greater than
4 % for high luminance over 10 cd/rn2 and not be greater than 10 % for low luminance of
10 cd/m2 and below.
2) Colorimetric luminance meter: the spectral responsivity shall comply with the colour- matching functions for the CIE 1931 standard colorimetric observer (see ISOICIE 11664-1) with chromaticity accuracy of 0,004 for x, v.
3) 2D imaging luminance meter: the number of pixels of the imaging detector shall be 4 times of the image subpixel within the measurement field as given in following each item. When a large measurement field angle is applied, it shall be noted that the measured luminance might be different between the centre and edge field. The digitalization dynamic range shall not be smaller than 12 bit per sample, The spectral responsivity shall comply with the CIE photopic luminous efficiency function, and the general 1(A) mismatch index/’. shall be not higher than 6 %.
4) Spectral radiance meter: The narrow spectral line widths of the laser projection displays usually require the use of a spectral radiance meter for accurate results of luminance and chromaticity. The requirements are as follows:
— the wavelength accuracy shall be within ± 0,5 nm;
— the wavelength measuring range shall be at least 380 nm to 780 nm;
— the stray light shall be less than 10
— The sampling interval shall be set to 1/N (N is an integer) of the spectral bandwidth of the spectroradiometer referred to in CIE 63 to achieve uniform spectral sampling function for accurate results. For example, a 2,5 nm sampling interval can be used for a 2,5 nm or 5 nm bandwidth.
It is recommended to use a spectroradiometer with a spectral bandwidth of not more than 5nm.IEC 62906-5-3 pdf free download.
