Rangefinding scope teardown

Anatomy of a laser rangefinding scope

A rangefinding scope is four subsystems and one optical budget: the day-optics you aim through, the laser that measures, the detector that receives the return, and the electronics that time it. Pick a part from the bill of materials and drop it on the scope - each parameter comes with the catalogue parts that carry it.

이 페이지 사용법
  1. 1부품표에서 부품 하나를 고릅니다.
  2. 2모듈 위에 놓거나 카드를 그냥 클릭합니다.
  3. 3그 역할과 파라미터, 그리고 이를 담당하는 모델명을 읽습니다.

부품표

모든 부품이 하나의 광학 버짓 안에 있습니다. 카드를 사진 위로 끌어 놓거나 클릭하십시오. 옆 패널이 그 부품의 파라미터로 채워집니다.

A laser rangefinding scope: objective on the left, eyepiece on the right, two windows on the bay above the objective, turret housing in the middle

여기로 부품을 끌어 놓기 또는 부품표에서 카드를 클릭

Objective on the left, eyepiece on the right. The two windows on the bay above the objective are the transmit and receive apertures; the driver and timing electronics sit in the saddle under the turret housing.

부품 위치는 교육용 도식이며 조립도가 아닙니다. 배치와 분해 보기는 참고용입니다. 파라미터 값은 링크된 사양의 값입니다.

모든 부품을 파라미터별로

인터랙티브 보기와 같은 수치를 읽고 검색하고 인용할 수 있는 표로 정리했습니다.

905 nm laser diode Transmitter

Emits the ranging pulse through the window above the objective. Peak power, pulse width, divergence and emission timing together set the reach and the power budget of a battery-powered device.

905 nm laser diode - Laser Diode | edge emitter
Peak wavelength 905 nm (895 - 915 nm)
Peak output power 40 - 600 W
Pulse energy @ 100 ns 4 - 30 uJ
Beam divergence, FWHM 9 x 25 deg bare | 9 x 6 deg FAC
Pulse width 1 - 100 ns (max 100 ns)
Duty cycle, max 0.1 %
Repetition rate up to 10 kHz
Package TO56 | metal stack | bare die
Operating temperature -40 to +85 C
Eye-safe alternative 1535 nm, >= 40 uJ up to 1 mJ

Avalanche photodiode Receiver

Sets how faint a return the scope can still see. Sensitivity has to be read together with responsivity, gain, dark current, bandwidth, bias stability and the receive aperture - never as one number.

Avalanche photodiode - Avalanche Photodiode | silicon
Response spectrum 400 - 1100 nm
Wavelength 905 nm
Active diameter 230 um | 500 um | 16 elements
Responsivity 80 A/W @ M=100
Response time 0.5 ns
Dark current 0.4 nA @ M=100
Total capacitance 1.0 pF @ M=100
Optimum gain 100
Reverse breakdown voltage 100 - 200 V
Voltage temp. coefficient 0.9 - 1.4 V/C
Optical filter 905 nm spike filter | band-pass
Package TO-46 | LCC1 / LCC2 ceramic | linear array
Eye-safe alternative InGaAs APD at 1550 nm, 9.5 A/W at M=10

Day and ranging optics Optics

Magnification, field of view and eye relief come from the objective and eyepiece; the two ranging windows set the transmit divergence and how much of the return reaches the detector.

Day and ranging optics - Objective, eyepiece and ranging paths
Optical channels 2 ranging (transmit + receive) + observation path
Aperture size (w x h) 110 x 30 um
Transmit beam, bare 9 x 25 deg FWHM
Transmit beam, FAC 9 x 6 deg FWHM
Receive aperture / focal length Set by your mechanical design
Receive filtering 905 nm band-pass at the detector
Windows on the bay 2

Control and timing electronics Electronics

Decides the pulse shape - width, rise time, jitter - and the receive bandwidth. Those two numbers are what the range resolution is actually made of.

Control and timing electronics - LD driver and return-signal processing
Peak pulse current 70 A
Pulse width 50 ns - 1 us adjustable
Repetition rate 1 kHz - 30 kHz adjustable
Rise time 7.5 ns typical
Fall time 12 ns typical
Supply voltage 12 V DC
Laser drive voltage 1 - 50 V DC
Control interface Internal trigger / external TTL
Factory default 100 ns @ 3 kHz, internal trigger
Eye-safe driver option 1535 nm: 10 A / 30 A pulsed, 1 / 5 / 10 Hz

이 페이지의 모든 파라미터 값은 링크된 제품 페이지를 생성하는 카탈로그 기록에서 가져오므로 둘이 어긋날 수 없습니다.

이 파라미터를 뒷받침하는 부품

아래 모든 수치는 링크된 제품 페이지를 생성하는 것과 동일한 카탈로그 기록에서 읽습니다. 이 페이지에서 다시 적은 값은 없습니다.

This scope is the 905 nm / pulsed / rangefinder scenario

Run the selector with application = rangefinder, wavelength = 905 nm and output = pulsed and it returns the transmit chain listed below. For a longer reach, or for a build that has to be eye-safe, the same four subsystems take a 1535 nm transmitter and a 1550 nm receiver - the catalogue carries both chains.

Scope optics and the eye-safe option

Tell us the range, the target and the size limit. We come back with the transmit chain, the receiver and the optics between them - at 905 nm, or eye-safe at 1535 nm.

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