HDL™- 64E - Velodyne Lidar

N = [Rotation Factor] * [Sequential Duty Cycle] * [Head Overlap] * [Illumination Duration] /
[T i ]
C 5 = N -0.25
Case a: C 5 = {.0255 * 0.75 * 2 * 10 [s] / 18 [us]} -0.25 = .083
Case b: C 5 = {.0145 * 0.75 * 2 * 10 [s] / 18 [us]} -0.25 = .095
Case c: C 5 = {.0059 * 0.75 * 2 * 10 [s] / 18 [us]} -0.25 = .119
Case d: C 5 = {31.25 [kHz] * 1 * 1 * 0.75 *.0004 * 10[s]} -0.25 = .321
The limits are then calculated by:
AEL train, SP = AEL SP * C 5 = 514 nJ
AEL train, SP = AEL 18us * C 5
Class 1M AEL 18us = 7 * 10 -4 * t 0.75 * C 4 (from IEC 60285-1 Table 4)
Where t = 18 us and C4 = 2.57
= 497 nJ
Class 1M
Case a: AEL train, SP 1M = 497 nJ * .083 = 41.3 nJ
Case b: AEL train, SP 1M = 497 nJ * .095 = 47.2 nJ
Case c: AEL train, SP 1M = 497 nJ * .119 = 59.1 nJ
Case d: AEL train, SP 1M = 514 nJ * .321 = 165.0 nJ
Condition 3 Conclusion
Since all Cases are lower than the Class 1M AEL train, SP , the Product is rated as Class 1M for
this Condition.
Condition 3B: Repetitive Pulse Accessible Emission Limit (18 us exposure)
Since there are multiple pulses within an 18 us period, we must also check that the total
energy in the 18 us period does not exceed the AEL for 18us.
Also, since there is no overlap of multiple laser emissions, there is no burst mode operation
in 18 us for Cases d, so this Case will not be evaluated in this calculation.
The maximum number of laser emissions that can occur in an 18 us period is:
Case a: 5
Case b: 5
Case c: 3
So, the total energy in this 18 us period is:
Sub-Case a: 5 * Detected Laser Energy SP = 5 * 32.1 nJ = 160.5 nJ
Sub-Case b: 5 * Detected Laser Energy SP = 5 * 31.6 nJ = 158.0 nJ
Sub-Case b: 5 * Detected Laser Energy SP = 3 * 22.7 nJ = 68.1 nJ
Class 1M AEL 18us = 7 * 10 -4 * t 0.75 * C 4 (from IEC 60285-1 Table 4)
Where t = 18 us and C4 = 2.57
= 497 nJ
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