The Nikon SB-5000 flash was released in 2016. It is Nikon's flagship Speedlight and with an air-cooling system.

I had the opportunity to dismantle this high-end Speedlight in order to evaluate the design of their air-cooling system. c1x4

Nikon SB-5000 Speedlight Air-cooling system teardown

What I found in the SB-5000 is amazing. There are many new stuff applied in this Speedlight.
I didn't take photos of the device appearance so there is no full picture of it. I started from the upper part of swivel flash head removed and let the electrician discharge the capacitor to ensure work safety.

To ensure the functionality of the swivel hinge and the wiring, I didn't dismantle the plastic case of the capacitor.

If you try to disassemble the speedlight, please make sure the high-voltage capacitor inside the device was fully discharge. The capacitor can store energy for very long time without battery installed. So please be careful. Excessive voltage may burn your skin or cause serious injury.

Let's start with the lower part of the battery chamber. 4 pieces of screws at the bottom of the battery chamber have to be removed. They are next to the mounting foot (hot shoe).

After removing the screws, the plastic cover that supports the mounting foot can be detached.

The mounting foot of the SB-5000 is similar to other Nikon model.

Spring contact under the thick metal plate of the mounting shoe.

Internal view of the mounting shoe assembly. No new features within the mounting shoe, therefore I didn't explore this part further.

A soft gasket around the edge of the plastic cover. The gasket may be used to prevent the ingress of dust or moisture.

After removing the mounting shoe and some screws on the top side of the Front Shell, the Front Shell can be opened (right side of the picture). Two IR LED for AF-assist illumination is glued to the front shell.

---Advertisement

---

Some circuit boards are installed around the battery chamber. The circuit board with pink and cyan wires connected is the Auxiliary power supply board. The wires connected to the External power terminal on the Front Shell.

There is a Sync terminal (silver color) and a Light sensor for non-TTL auto flash installed on the lower left and right corner of the Front Shell.

Nikon SB-5000 flash head assembly and PCB

The black color IGBT circuit board lay on the white color Lamp Shade. A flexible printed circuit board (FPC) was used to connect the zoom motor and flash tube control circuit.
There are several wires and thermal sensor connected to the IGBT circuit board as well as the flash tube and reflector holder. I never see a speedlight with so many thermal sensors implant to the flash lamp unit.

Four piece of sensors and two key buttons are located on the FPC. They used to detect for the accessories such as Color filter or Bounce adapter. The setting of the speedlight seem to be adaptive change when an accessories was mounted to the flash head.

Flip the IGBT circuit board, a piece of transparent plastic at the middle of the Lamp Shade. It is the upper cover of the air supply line. The air come from the pump on the rear side of the Lamp Shade (the thin black color part is the pump).

This is the front and bottom view of the Lamp Shade.

Inside the Lamp Shade, there is a zoom head called Flash Lamp Unit. It consists of a dark gray color Reflector Holder, a stainless steel metal frame, a quartz glass window, a flash tube and a high polish metal reflector.

Usually, most of the Reflector Holder are made in white color plastic. But SB-5000 used an remarkable dark grey color plastic for this holder. The dark grey material seem to be a glass fiber reinforced grade high temperature engineering thermoplastic called PPS. It's service temperature up to 200 degC or more, much higher than the general plastic which used in other speedlight.

---Advertisement

---

The quartz glass window is mounted by a metal frame. The metal frame has wingtips on both sides to guide the air flowing straight through the glass window.

The metal plate near the bottom of the picture with marking "P66H" is a zoom motor. The zoom motor is sitting on the back side of the metal plate.

Two pieces of shafts located on the left and right sides of the zoom motor are the guide rails of the Flash Lamp Unit.

The Flash Lamp Unit is driven by a zoom motor which can slides back and forth on these guide rails to provide variable flash angle of coverage.

There is a micro switch on the FPC just between the mounting screws. It used to calibrate and detect the zoom position of the Flash Lamp Unit.

There are 3 small holes appear on the inner surface of the Lamp Shade just above the Flash Lamp Unit. The holes are the outlet of the air cooling system. It sprays air toward the glass windows and the acrylic Fresnel Lens. (the Fresnel lens not shown in the picture) .

Three small holes located at the forefront of the Lamp Shade is to supply cooling air to the acrylic Fresnel lens just in front of the Lamp Shade. (Fresnel lens not shown in picture)

The heart of the air cooling system is a piezoelectric micro-blower. It mounted on the rear side of the Lamp Shade.

The Mirco-blower model "Murata MZB1001" is a low profile air pump. (In fact, there is a filter box mounted on the pump. But I didn't take a picture of the filter.) The air flow rate of the pump is 1.2L/min (@21V dc).

The pump was glue and seal to the Lamp Shade by a clear adhesive tape.

The nozzle of the pump connect to the inlet and a L-shape canal on the Lamp Shade.

The canal was buried under the pump by an adhesive tape and a J-shape transparent plastic cover. The canal acting as a air supply line to transfer the pressurized air from the inlet to the outlet at the front of the Lamp Shade.

This is a top view of the Lamp Shade. The pressurized air flows from the rear side of the Lamp Shade passing through a J-shape canal toward the front edge. Near the front edge of the Lamp Shade, the canal divided into two direction, forming a T-shape canal.

Close-up of T-shape transparent plastic cover. It is a piece of plastic which stick to the Lamp Shade by adhesive tape and then reinforced by the adhesive glue put at the inner corners.

This picture shows the Lamp Shade with the transparent cover removed. The J-shape canal for pressurized air passage can be seen.

This picture is the top side of the transparent part.

This picture is the bottom side of the transparent part with a nozzle cover was attached to it. The nozzle cover is a component of the Lamp Shade.

Close-up of the nozzle cover. As you see there are 3 pin holes on it. Diameter of the holes is around 0.35mm. The holes are the outlet of the pressurized air for cooling.

By using the air pump and nozzles, the air cooling system can cool the flash head down. According to our experiments, the rapid firing of the flash tube will cause the acrylic Fresnel lens which mounted in front of the Lamp Shade to heat up. Heat will accumulate on the Fresnel lens and eventually melt it.

The air cooling system was designed to sprays air into the gap between the Flash Lamp Unit and the acrylic Fresnel lens to form an air circulation. The heat stored on the Fresnel lens dissipated through the air stream and spread inside the flash head. The cooling system is able to prevent hot spot and slow down the temperature rise of the Fresnel lens.

Since the power of the flash tube is much stronger than the air pump, the air cooling system cannot completely prevent the temperature of the Fresnel lens from rising. If the shooting speed exceeds the cooling speed of the Fresnel lens, the lens will eventually overheat.

Moreover, the flash head itself is a sealed environment to prevent dust from entering. Even a stronger pump and more air flow are used, the air temperature in the flash head will continue to rise, and the cooling effect will be reduced proportionally.

---Advertisement

---

Besides air-cooling system, there are more detail inside the flagship SB-5000 which you may interested.

On the left side of the battery compartment, there is a Light sensor circuit board to detect wireless remote control flash.

The number of circuit boards inside the SB-5000 is incredible. They occupy the space inside the housing. The circuit boards are connected by many wires and connectors. But the wiring and layout are very nice. It is not difficult to access the connectors and circuit boards.

The front shell can be removed by unplugging the three connectors.

There is a Radio circuit board (model 1EK) and Piezo buzzer element was mounted under the battery chamber. The radio circuit board is used for wireless communication.

The battery chamber was detached from the rear housing. The Main board can be seen. All buttons, rotary selector and LCD display are located on the opposite side of the board.

A huge copper radiator mounted on the inverter circuit board.

The Main board is full of electronic component.

Close-up of the micro coaxial cable. It is rare to use this kind of expensive cable for Speedlight. This cable responsible for the signal communication between the zoom motor and Filter sensor.

A new technology discovered in the SB-5000. This is the most complicated flash tube holder and flash lamp reflector structure I have ever seen.

The new technology is to use a swing Tilt Angle Holder to support the flash tube.

The Tilt Angle Holder enable the flash tube to move slightly back and fro inside the parabolic flash lamp reflector.

---Advertisement

---

The flash tube slightly shift always from the focal point of the lamp reflector to achieve off-axis reflection of the light. Depends on the range of the off-axis, the flash head able to create parallel and convergent beam of light.

The tilt angle of the Tilt Angle Holder is controlled by the plastic rib sliding on the wedge-shaped rail on the Lamp Shade. The tilt angle of the holder is depends on the zoom distance of the flash head setting.

The Flash Lamp Unit is driven by the zoom motor as shown above. There is a rectangular shape slot on Flash Lamp Unit which allow the metallic tongue of the zoom motor slider to fit in. The metallic tongue with high precision position control move along the leading screw which was driven by the miniature zoom motor.

If you want to replace the flash tube. It will be easier to have the whole Flash Lamp Unit unload from the Lamp Shade by pull out the two shafts as shown above.

The flash tube was sealed inside a milky rubber sleeve by some white color silicone glue. Both ends of the flash tube was supported firmly inside the Tilt Angle Holder.

Desolder the cables which connected to the IGBT board.

By removing the silicone glue, the flash tube can be unloaded from the Tilt Angle Holder.

A huge sensor is glued to the back of the reflector holder. It may be a thermal sensor to detect the temperature of the Reflector. The fins on the Reflector Holder seem to be used for heat dissipation.