How thin is a 1.33 inch Sharp Memory TFT display?
Let me cut straight to the chase: the 1.33 inch Sharp Memory TFT display measures just 0.98 mm in thickness—that’s less than a millimeter, about the same as two sheets of standard printer paper stacked together. This ultra-slim profile is a direct result of Sharp’s proprietary Memory-in-Pixel (MIP) technology, which eliminates the need for bulky backlight assemblies and thick glass layers. Unlike conventional TFT LCDs that require a separate backlight unit, this display integrates pixel memory directly into the panel, allowing it to hold an image with zero power draw while still delivering a crisp 128x128 resolution. The total module weight is around 4.5 grams, and its dimensions are 34.2 mm x 34.2 mm x 0.98 mm, making it one of the thinnest fully functional color displays on the market for embedded systems.
To put that in perspective, compare it to other common display types. A typical 1.5-inch OLED module, like those used in smartwatches, often comes in at 1.2 mm to 1.5 mm thick due to the glass encapsulant and polarizer layers. Even the thinnest e-paper displays, like those from E Ink, hover around 1.0 mm to 1.2 mm. The Sharp Memory TFT undercuts them all, but it does so without sacrificing durability. The glass substrate is only 0.5 mm thick, and the color filter layer adds another 0.2 mm, with the remaining 0.28 mm accounting for the polarizer, adhesive, and protective coating. This stacking is remarkably efficient, and the panel uses a reflective design—meaning it relies on ambient light instead of a backlight—so there’s no need for a light guide plate or diffuser film, which would add at least 0.5 mm to the total thickness.
Now, let’s get into the engineering details that make this possible. The 1.33 inch sharp memory tft display uses a low-temperature polysilicon (LTPS) TFT backplane, which is inherently thinner than the amorphous silicon used in standard TFTs. LTPS allows for smaller transistors and tighter pixel pitch, so the driving circuitry can be integrated directly onto the glass, reducing the need for external flex cables or thick PCB attachments. The pixel pitch is 0.26 mm, giving you 128x128 pixels in a 1.33-inch diagonal, which translates to a pixel density of about 135 PPI. That’s not retina-level, but it’s perfectly readable for icons, text, and simple graphics, especially given the display’s 8-color capability (RGB with 2 bits per channel). The memory layer is a 1-bit SRAM per pixel, which holds the last state even when the display is powered off, and the refresh rate can be as low as 1 Hz for static images—this drastically cuts power consumption to about 0.1 mW for a static image, compared to 10-20 mW for a comparable backlit TFT.
Let’s break down the physical stack with some hard numbers. The display consists of four main layers: the bottom polarizer (0.1 mm), the LTPS TFT glass substrate (0.5 mm), the color filter array (0.2 mm), and the top polarizer with anti-glare coating (0.18 mm). Total: 0.98 mm, plus or minus 0.05 mm manufacturing tolerance. The interface is a 24-pin FPC (flexible printed circuit) that’s 0.3 mm thick and 10 mm wide, but that’s not included in the panel thickness measurement because it extends off the edge. The FPC uses a standard 0.5 mm pitch connector, and the operating temperature range is -20°C to +70°C, which is typical for consumer electronics but impressive for such a thin glass structure. The display also has a 1.0 mm border around the active area, so the overall footprint is 34.2 mm x 34.2 mm, but the active area itself is 30.0 mm x 30.0 mm. That’s a 77% active area ratio, which is high for a display this small.
Now, why does this thinness matter in real-world applications? Let’s look at three common use cases: smart cards, wearable sensors, and IoT tags. For a smart card, the total thickness limit is usually 0.76 mm for ISO/IEC 7810 ID-1 cards, but that’s for the entire card including the chip and antenna. A 0.98 mm display is too thick to embed flush into a standard card, but it can be used in thicker cards or as a surface-mount module. For wearables like a fitness band, the display thickness directly impacts the device profile. A 0.98 mm panel allows the overall device to be under 5 mm thick, which is competitive with the thinnest smartwatches. For IoT tags, like those used in warehouse asset tracking, the thinness means the tag can be attached to curved surfaces or placed inside slim enclosures without adding noticeable bulk. The reflective nature also means no backlight power drain, so a small coin cell battery like a CR2032 can power the display for months with intermittent updates.
Let’s compare the Sharp Memory TFT to other ultra-thin displays in a table:
| Display Type | Thickness (mm) | Resolution | Power (static) | Backlight |
|---|---|---|---|---|
| Sharp Memory TFT 1.33" | 0.98 | 128x128 | 0.1 mW | None (reflective) |
| Standard 1.5" TFT LCD | 1.5 - 2.0 | 128x128 | 15 mW | LED backlight |
| 1.3" OLED (monochrome) | 1.2 - 1.5 | 128x64 | 0.5 mW | None (emissive) |
| E Ink 1.54" | 1.0 - 1.2 | 200x200 | 0.0 mW (static) | None (reflective) |
| Sharp Memory LCD 1.28" | 1.1 | 128x128 | 0.1 mW | None (reflective) |
Notice that the Sharp Memory TFT is actually thinner than the Sharp Memory LCD (which uses a different backplane technology) by about 0.12 mm. That’s because the Memory TFT uses a more streamlined color filter process. The color filter for the TFT version is applied directly to the TFT array using a photo-lithographic method, rather than being a separate glass layer bonded to the TFT. This eliminates one full glass-to-glass lamination step, saving both thickness and cost. The trade-off is that the color gamut is limited to about 30% of NTSC, which is fine for basic color coding but not for photo-quality images. The contrast ratio is about 10:1 in reflective mode, which is typical for reflective color displays—you’ll get readable colors under direct sunlight, but in dim light, you’ll need a front light, which isn’t included in the module.
One more thing about the thinness: it affects the mechanical handling. The 0.5 mm glass substrate is fragile if you apply point pressure, so the display is typically shipped with a protective film that’s 0.05 mm thick. The film adds a negligible amount to the total thickness but prevents scratches during assembly. The display also has a VCOM electrode that’s only 0.1 microns thick—that’s 100 nanometers—which is a sputtered layer of indium tin oxide (ITO) on the color filter. This layer is what drives the liquid crystal alignment, and it’s so thin that it’s essentially invisible to the naked eye. The liquid crystal layer itself is only 3 microns thick, which is about 1/30th the thickness of a human hair. That’s what allows the display to switch pixels in under 10 milliseconds, even at low voltage.
If you’re integrating this into a product, you need to account for the 0.98 mm thickness in your enclosure design. The display has a 0.5 mm tolerance on the glass edge, so you should leave at least 0.2 mm of clearance on all sides to avoid chipping. The FPC exit point is at the bottom edge, and it bends at a 90-degree angle, so you’ll need at least 3 mm of vertical clearance for the cable to route without stress. The display is also sensitive to static discharge, so you’ll want to include an ESD protection diode on the data lines. The interface is SPI (Serial Peripheral Interface) with a maximum clock speed of 10 MHz, so you can update the entire 128x128 frame in about 16 milliseconds if you’re sending raw pixel data. The display supports partial updates, so you can change only a portion of the screen to save power.
Let’s talk about the real-world thickness in context of a finished product. Suppose you’re building a smart badge that shows a QR code and a name. The display sits on top of a 0.8 mm thick PCB, with a 0.1 mm adhesive layer between them. The total stack is 0.98 + 0.1 + 0.8 = 1.88 mm. Add a 0.5 mm front cover glass and a 0.5 mm back cover, and the badge is about 2.88 mm thick. That’s thinner than a typical credit card (which is 0.76 mm), but remember the badge has a battery and microcontroller. A CR2032 battery is 3.2 mm thick, so you’d need to offset the display or use a thinner battery like a CR1225 (1.6 mm). The point is, the display’s thinness gives you flexibility to design a slim device without compromise.
One more data point: the display’s total optical stack thickness, including the polarizer and color filter, is only 0.38 mm. That’s the distance from the top glass surface to the liquid crystal layer. This shallow optical path means the viewing angle is limited to about 80 degrees in the horizontal and vertical directions, but the reflective nature means you don’t get the color shift that plagues backlit displays. The display also has a transflective mode if you add a front light, but that’s not included in the standard module. Some third-party suppliers offer a front light module that adds 0.5 mm, bringing the total to 1.48 mm, but that’s still thinner than most backlit TFTs.
In terms of durability, the glass is chemically strengthened to about 400 MPa surface compression, which is similar to Gorilla Glass 3 but without the ion-exchange treatment. The display can withstand a 10 cm drop onto a hard surface without cracking, but you wouldn’t want to test it. The operating humidity range is 10% to 90% non-condensing, and the storage temperature range is -30°C to +80°C. The display’s thinness doesn’t compromise its environmental resistance because the sealant around the edges is a UV-cured epoxy that’s only 0.1 mm wide, but it forms a hermetic barrier against moisture and dust.
I should also mention that the display’s 0.98 mm thickness is measured at the center of the panel, but the edges are slightly thicker due to the sealant bead. The sealant adds about 0.05 mm to the edge thickness, so the maximum thickness at the perimeter is 1.03 mm. This is within the typical tolerance for glass displays, but it’s something to consider if you’re designing a tight-fit bezel. The display is also available with an optional adhesive backing that adds 0.1 mm, but most designers prefer to use their own mounting method.
To give you a sense of the manufacturing precision, the glass substrate is cut using a laser scribe and break process, which creates a slight edge bevel of about 0.1 mm. This bevel is not sharp enough to cut your finger, but it’s not perfectly square either. The FPC is bonded to the glass using anisotropic conductive film (ACF), which is about 0.05 mm thick after pressing. The bonding process requires a temperature of 180°C and a pressure of 2 MPa for 10 seconds, which is standard for small displays. The ACF bond has a pull strength of about 5 N per pin, so it’s mechanically robust despite the thinness.
Finally, let’s look at the power implications of the thin design. Because there’s no backlight, the display doesn’t generate heat, so you don’t need a heatsink or ventilation. This allows the display to be placed directly against a battery or PCB without thermal concerns. The thin glass also means the display has a lower thermal mass, so it reaches thermal equilibrium faster when the ambient temperature changes. This is important for outdoor applications where the display might be exposed to direct sunlight. The reflective nature means the display actually works better in bright light, unlike emissive displays that wash out. The 0.98 mm thickness is a key enabler for this performance, because it allows the display to be mounted flush with the device surface, reducing glare and improving readability.
In summary, the 1.33 inch Sharp Memory TFT display’s 0.98 mm thickness is a result of advanced LTPS backplane technology, a single-glass color filter process, and the elimination of a backlight layer. It’s one of the thinnest color displays available for embedded applications, and it offers a unique combination of ultra-low power, sunlight readability, and compact form factor. The numbers speak for themselves: 0.98 mm, 4.5 grams, 0.1 mW static power, and a 128x128 resolution that fits in a 34.2 mm square footprint. If you’re designing a product where every millimeter counts, this display is a strong candidate.