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US-20260126470-A1 - DYNAMIC PROBE COLORING AND STATUS INFORMATION USING PASSIVE OPTICAL FIBER

US20260126470A1US 20260126470 A1US20260126470 A1US 20260126470A1US-20260126470-A1

Abstract

A probe may include a probe head with a probe tip for connecting to a device under test (DUT), and a probe body for electro-mechanically connecting to a channel of a test and measurement instrument, the channel having a pre-assigned color identifier. The probe may include a probe cable connected between the probe head and the probe body. The probe may include a light source, and an optical fiber having a first end coupled to the light source and a second end coupled to the probe head. The probe head has a channel indicator coupled to the optical fiber. The probe has communication and control circuitry configured to, when the probe is connected to the channel of the test and measurement instrument, cause the light source and the channel indicator to illuminate in a color matching the color identifier of the channel.

Inventors

  • Jackson R. Brooke
  • Jeffrey D. Miller
  • Barton T. Hickman

Assignees

  • TEKTRONIX, INC.

Dates

Publication Date
20260507
Application Date
20251107

Claims (20)

  1. 1 . A test and measurement probe, comprising: a probe head including a housing, and a probe tip for electrically connecting to a device under test (DUT); a probe body including a connection interface for electro-mechanically connecting to a channel of a test and measurement instrument, the channel having a pre-assigned color identifier; a probe cable connected between the probe head and the probe body, the probe cable having a length; a light source; an optical fiber having a first end coupled to the light source and a second end coupled to the probe head, the optical fiber running substantially parallel to the probe cable; a channel indicator visible to a user at an exterior surface of the housing of the probe head, the channel indicator coupled to the optical fiber; and communication and control circuitry configured to, when the connection interface is connected to the channel of the test and measurement instrument, cause the light source and the channel indicator to illuminate in a color matching the color identifier of the channel.
  2. 2 . The test and measurement probe of claim 1 , wherein the channel indicator comprises an optical diffuser.
  3. 3 . The test and measurement probe of claim 2 , wherein the optical diffuser comprises a translucent portion of the housing of the probe head.
  4. 4 . The test and measurement probe of claim 3 , wherein the translucent portion comprises a translucent ring around a perimeter of the housing of the probe head.
  5. 5 . The test and measurement probe of claim 1 , wherein the probe tip is located at a first exterior surface of the housing of the probe head, and the channel indicator is located on one or more exterior surfaces of the housing different than the first exterior surface.
  6. 6 . The test and measurement probe of claim 1 , wherein the probe head comprises only passive circuit components.
  7. 7 . The test and measurement probe of claim 1 , wherein the light source is located in the probe body.
  8. 8 . The test and measurement probe of claim 1 , wherein the light source is located in the test and measurement instrument, and the connection interface includes an optical connector to couple the light source to the optical fiber.
  9. 9 . The test and measurement probe of claim 1 , wherein the optical fiber comprises a plurality of optical fibers, each optical fiber having a first end coupled to the light source and a second end coupled to the probe head.
  10. 10 . The test and measurement probe of claim 1 , wherein the optical fiber is mechanically connected to the probe cable at discrete locations along the length of the probe cable.
  11. 11 . The test and measurement probe of claim 1 , wherein the optical fiber is mechanically connected to the probe cable continuously along the length of the probe cable.
  12. 12 . The test and measurement probe of claim 1 , wherein the probe cable includes a slot along the length of the probe cable, and the optical fiber is inserted into the slot.
  13. 13 . The test and measurement probe of claim 1 , wherein the probe cable and the optical fiber are enclosed together in a common cable sleeve.
  14. 14 . The test and measurement probe of claim 13 , wherein one or more portions of the common cable sleeve are translucent.
  15. 15 . The test and measurement probe of claim 1 , wherein at least a portion of the optical fiber comprises a light-diffusing fiber.
  16. 16 . The test and measurement probe of claim 15 , wherein the light-diffusing fiber is visible to a user.
  17. 17 . The test and measurement probe of claim 1 , wherein the communication and control circuitry is further configured to cause the light source to produce a pattern of light, to illuminate in a specific intensity, or to illuminate in a specific color in response to at least one of an input from a user and an instruction from the test and measurement instrument.
  18. 18 . A method of visually identifying a test and measurement probe connected to a channel of a test and measurement instrument, the channel having a pre-assigned color identifier, the method comprising: causing a light source to illuminate in a color matching the color identifier of the channel, the light source being coupled to a first end of an optical fiber in a probe body of the test and measurement probe, the optical fiber running substantially parallel to an electrical probe cable of the test and measurement probe; transmitting the light from the light source through the optical fiber to a second end of the optical fiber in a probe head of the test and measurement probe; and diffusing the light at the probe head so that the color is visible to a user at the probe head.
  19. 19 . The method of claim 18 , wherein transmitting the light from the light source comprises diffusing the light along at least a portion of a length of the optical fiber so that the light is visible to a user along the portion of the length.
  20. 20 . The method of claim 18 , further comprising: causing the light source to produce a pattern of light, to illuminate in a specific intensity, or to illuminate in a specific color in response to at least one of an input from the user and an instruction from the test and measurement instrument.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application is a non-provisional of, and claims priority to, U.S. Provisional Pat. App. No. 63/717,791, filed Nov. 7, 2024, which is hereby incorporated by reference in its entirety. TECHNICAL FIELD This disclosure relates to test and measurement systems, and more particularly to test and measurement probes. BACKGROUND Test and measurement probe users often have multiple probes connected to a device under test (DUT) for measuring various signals. The other ends of the probes are each connected to different input channels of a test and measurement instrument, such as an oscilloscope. The signal received at each channel of the instrument is typically presented on the instrument's display in a unique assigned color or style, so a user can easily visually distinguish the different displayed signals. For example, the signal received at channel one of the instrument may be displayed in a yellow color, the signal received at channel two of the instrument may be displayed in blue, channel three in red, channel four in green, etc. When several probes are connected to a DUT, their cables can easily get tangled, especially if the probes are moved from one test point to another, and it can be difficult to visually determine which probe is physically connected to which input on the test and measurement instrument. To help users associate a probe with the channel to which it is connected, currently, some probe manufacturers include small plastic color rings with passive probes to allow users to associate the probe head and probe body. A similar approach can be taken for probes in other categories, but all solutions today require manual installation. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram of plastic colored rings sometimes used for probe identification. FIG. 2 is a block diagram of a test and measurement probe connected to a first channel of a test and measurement instrument, according to embodiments of the disclosure. FIG. 3 is a block diagram of a test and measurement probe connected to a second channel of a test and measurement instrument, according to embodiments of the disclosure. FIG. 4 is a block diagram of a test and measurement probe according to some embodiments of the disclosure. FIG. 5 is a block diagram of a test and measurement probe according to some embodiments of the disclosure. FIG. 6 is a block diagram of a test and measurement probe according to some embodiments of the disclosure. FIG. 7 is a block diagram of a test and measurement probe according to some embodiments of the disclosure. DETAILED DESCRIPTION Test and measurement probes can be divided into two categories: active and passive. Active probes use circuit components in the probe that require external power. Passive probes do not. For example, active probes typically include a powered component such as an amplifier, usually located as physically close to the probe tip/probing point as possible. In contrast, passive probes typically include only passive circuit components such as resistors and capacitors, especially at the probe tip. Some passive probes do include some powered components in the probe body, or “compbox” end that connects to the test and measurement instrument. For example, a memory device, such as an EEPROM, and some communication circuitry may be located in the probe body. The memory device can store an identifier of the probe type, such as a model number, and/or other attributes of the probe, such as an attenuation factor. When the probe is connected to the test and measurement instrument, power may be supplied through the connection interface from the test and measurement instrument to communication circuitry in the compbox to, for example, read the memory device. This allows the test and measurement instrument to recognize the probe type, and/or probe attribute, and automatically apply particular settings appropriate for that probe, for example vertical gain/scale settings, unit of measure settings, bandwidth limit, etc. Active probes generally provide higher bandwidth, higher performance, lower input impedance, and lower circuit loading than passive probes. However, passive probes are simpler, rugged, and lower cost, and are therefore quite suitable for general purpose DUT probing needs. FIG. 1 shows an example of the plastic rings 160, 161, 162 currently used with some passive probes, intended to associate the probe head at one end of the cable with the probe body at the other. The probe 100 of FIG. 1 has a probe head 110 with a probe tip 112 extending from the probe head to make electrical contact with a test point on a DUT. The probe head is connected to a probe body 120 by a probe cable 130. The probe cable is typically a coaxial cable between 1 meter and 3 meters long, but other cable types and lengths are possible. The probe body 120 is the part of the probe that connects to a test and measurement instrument, for example connecting to an input channel on an osc